/* cairo - a vector graphics library with display and print output * * Copyright © 2002 University of Southern California * Copyright © 2005 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it either under the terms of the GNU Lesser General Public * License version 2.1 as published by the Free Software Foundation * (the "LGPL") or, at your option, under the terms of the Mozilla * Public License Version 1.1 (the "MPL"). If you do not alter this * notice, a recipient may use your version of this file under either * the MPL or the LGPL. * * You should have received a copy of the LGPL along with this library * in the file COPYING-LGPL-2.1; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA * You should have received a copy of the MPL along with this library * in the file COPYING-MPL-1.1 * * The contents of this file are subject to the Mozilla Public License * Version 1.1 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY * OF ANY KIND, either express or implied. See the LGPL or the MPL for * the specific language governing rights and limitations. * * The Original Code is the cairo graphics library. * * The Initial Developer of the Original Code is University of Southern * California. * * Contributor(s): * Carl D. Worth */ #include "cairoint.h" #include "cairo-clip-inline.h" #include "cairo-clip-private.h" #include "cairo-error-private.h" #include "cairo-list-inline.h" #include "cairo-gstate-private.h" #include "cairo-pattern-private.h" #include "cairo-traps-private.h" #if _XOPEN_SOURCE >= 600 || defined (_ISOC99_SOURCE) #define ISFINITE(x) isfinite (x) #else #define ISFINITE(x) ((x) * (x) >= 0.) /* check for NaNs */ #endif static cairo_status_t _cairo_gstate_init_copy (cairo_gstate_t *gstate, cairo_gstate_t *other); static cairo_status_t _cairo_gstate_ensure_font_face (cairo_gstate_t *gstate); static cairo_status_t _cairo_gstate_ensure_scaled_font (cairo_gstate_t *gstate); static void _cairo_gstate_unset_scaled_font (cairo_gstate_t *gstate); static void _cairo_gstate_transform_glyphs_to_backend (cairo_gstate_t *gstate, const cairo_glyph_t *glyphs, int num_glyphs, const cairo_text_cluster_t *clusters, int num_clusters, cairo_text_cluster_flags_t cluster_flags, cairo_glyph_t *transformed_glyphs, int *num_transformed_glyphs, cairo_text_cluster_t *transformed_clusters); static void _cairo_gstate_update_device_transform (cairo_observer_t *observer, void *arg) { cairo_gstate_t *gstate = cairo_container_of (observer, cairo_gstate_t, device_transform_observer); gstate->is_identity = (_cairo_matrix_is_identity (&gstate->ctm) && _cairo_matrix_is_identity (&gstate->target->device_transform)); } cairo_status_t _cairo_gstate_init (cairo_gstate_t *gstate, cairo_surface_t *target) { VG (VALGRIND_MAKE_MEM_UNDEFINED (gstate, sizeof (cairo_gstate_t))); gstate->next = NULL; gstate->op = CAIRO_GSTATE_OPERATOR_DEFAULT; gstate->opacity = 1.; gstate->tolerance = CAIRO_GSTATE_TOLERANCE_DEFAULT; gstate->antialias = CAIRO_ANTIALIAS_DEFAULT; _cairo_stroke_style_init (&gstate->stroke_style); gstate->fill_rule = CAIRO_GSTATE_FILL_RULE_DEFAULT; gstate->font_face = NULL; gstate->scaled_font = NULL; gstate->previous_scaled_font = NULL; cairo_matrix_init_scale (&gstate->font_matrix, CAIRO_GSTATE_DEFAULT_FONT_SIZE, CAIRO_GSTATE_DEFAULT_FONT_SIZE); _cairo_font_options_init_default (&gstate->font_options); gstate->clip = NULL; gstate->target = cairo_surface_reference (target); gstate->parent_target = NULL; gstate->original_target = cairo_surface_reference (target); gstate->device_transform_observer.callback = _cairo_gstate_update_device_transform; cairo_list_add (&gstate->device_transform_observer.link, &gstate->target->device_transform_observers); gstate->is_identity = _cairo_matrix_is_identity (&gstate->target->device_transform); cairo_matrix_init_identity (&gstate->ctm); gstate->ctm_inverse = gstate->ctm; gstate->source_ctm_inverse = gstate->ctm; gstate->source = (cairo_pattern_t *) &_cairo_pattern_black.base; /* Now that the gstate is fully initialized and ready for the eventual * _cairo_gstate_fini(), we can check for errors (and not worry about * the resource deallocation). */ return target->status; } /** * _cairo_gstate_init_copy: * * Initialize @gstate by performing a deep copy of state fields from * @other. Note that gstate->next is not copied but is set to %NULL by * this function. **/ static cairo_status_t _cairo_gstate_init_copy (cairo_gstate_t *gstate, cairo_gstate_t *other) { cairo_status_t status; VG (VALGRIND_MAKE_MEM_UNDEFINED (gstate, sizeof (cairo_gstate_t))); gstate->op = other->op; gstate->opacity = other->opacity; gstate->tolerance = other->tolerance; gstate->antialias = other->antialias; status = _cairo_stroke_style_init_copy (&gstate->stroke_style, &other->stroke_style); if (unlikely (status)) return status; gstate->fill_rule = other->fill_rule; gstate->font_face = cairo_font_face_reference (other->font_face); gstate->scaled_font = cairo_scaled_font_reference (other->scaled_font); gstate->previous_scaled_font = cairo_scaled_font_reference (other->previous_scaled_font); gstate->font_matrix = other->font_matrix; _cairo_font_options_init_copy (&gstate->font_options , &other->font_options); gstate->clip = _cairo_clip_copy (other->clip); gstate->target = cairo_surface_reference (other->target); /* parent_target is always set to NULL; it's only ever set by redirect_target */ gstate->parent_target = NULL; gstate->original_target = cairo_surface_reference (other->original_target); gstate->device_transform_observer.callback = _cairo_gstate_update_device_transform; cairo_list_add (&gstate->device_transform_observer.link, &gstate->target->device_transform_observers); gstate->is_identity = other->is_identity; gstate->ctm = other->ctm; gstate->ctm_inverse = other->ctm_inverse; gstate->source_ctm_inverse = other->source_ctm_inverse; gstate->source = cairo_pattern_reference (other->source); gstate->next = NULL; return CAIRO_STATUS_SUCCESS; } void _cairo_gstate_fini (cairo_gstate_t *gstate) { _cairo_stroke_style_fini (&gstate->stroke_style); cairo_font_face_destroy (gstate->font_face); gstate->font_face = NULL; cairo_scaled_font_destroy (gstate->previous_scaled_font); gstate->previous_scaled_font = NULL; cairo_scaled_font_destroy (gstate->scaled_font); gstate->scaled_font = NULL; _cairo_clip_destroy (gstate->clip); cairo_list_del (&gstate->device_transform_observer.link); cairo_surface_destroy (gstate->target); gstate->target = NULL; cairo_surface_destroy (gstate->parent_target); gstate->parent_target = NULL; cairo_surface_destroy (gstate->original_target); gstate->original_target = NULL; cairo_pattern_destroy (gstate->source); gstate->source = NULL; VG (VALGRIND_MAKE_MEM_NOACCESS (gstate, sizeof (cairo_gstate_t))); } /** * _cairo_gstate_save: * @gstate: input/output gstate pointer * * Makes a copy of the current state of @gstate and saves it * to @gstate->next, then put the address of the newly allcated * copy into @gstate. _cairo_gstate_restore() reverses this. **/ cairo_status_t _cairo_gstate_save (cairo_gstate_t **gstate, cairo_gstate_t **freelist) { cairo_gstate_t *top; cairo_status_t status; if (CAIRO_INJECT_FAULT ()) return _cairo_error (CAIRO_STATUS_NO_MEMORY); top = *freelist; if (top == NULL) { top = malloc (sizeof (cairo_gstate_t)); if (unlikely (top == NULL)) return _cairo_error (CAIRO_STATUS_NO_MEMORY); } else *freelist = top->next; status = _cairo_gstate_init_copy (top, *gstate); if (unlikely (status)) { top->next = *freelist; *freelist = top; return status; } top->next = *gstate; *gstate = top; return CAIRO_STATUS_SUCCESS; } /** * _cairo_gstate_restore: * @gstate: input/output gstate pointer * * Reverses the effects of one _cairo_gstate_save() call. **/ cairo_status_t _cairo_gstate_restore (cairo_gstate_t **gstate, cairo_gstate_t **freelist) { cairo_gstate_t *top; top = *gstate; if (top->next == NULL) return _cairo_error (CAIRO_STATUS_INVALID_RESTORE); *gstate = top->next; _cairo_gstate_fini (top); VG (VALGRIND_MAKE_MEM_UNDEFINED (&top->next, sizeof (cairo_gstate_t *))); top->next = *freelist; *freelist = top; return CAIRO_STATUS_SUCCESS; } /** * _cairo_gstate_redirect_target: * @gstate: a #cairo_gstate_t * @child: the new child target * * Redirect @gstate rendering to a "child" target. The original * "parent" target with which the gstate was created will not be * affected. See _cairo_gstate_get_target(). **/ cairo_status_t _cairo_gstate_redirect_target (cairo_gstate_t *gstate, cairo_surface_t *child) { /* If this gstate is already redirected, this is an error; we need a * new gstate to be able to redirect */ assert (gstate->parent_target == NULL); /* Set up our new parent_target based on our current target; * gstate->parent_target will take the ref that is held by gstate->target */ gstate->parent_target = gstate->target; /* Now set up our new target; we overwrite gstate->target directly, * since its ref is now owned by gstate->parent_target */ gstate->target = cairo_surface_reference (child); gstate->is_identity &= _cairo_matrix_is_identity (&child->device_transform); cairo_list_move (&gstate->device_transform_observer.link, &gstate->target->device_transform_observers); /* The clip is in surface backend coordinates for the previous target; * translate it into the child's backend coordinates. */ _cairo_clip_destroy (gstate->clip); gstate->clip = _cairo_clip_copy_with_translation (gstate->next->clip, child->device_transform.x0 - gstate->parent_target->device_transform.x0, child->device_transform.y0 - gstate->parent_target->device_transform.y0); return CAIRO_STATUS_SUCCESS; } /** * _cairo_gstate_is_group: * @gstate: a #cairo_gstate_t * * Check if _cairo_gstate_redirect_target has been called on the head * of the stack. * * Return value: %TRUE if @gstate is redirected to a target different * than the previous state in the stack, %FALSE otherwise. **/ cairo_bool_t _cairo_gstate_is_group (cairo_gstate_t *gstate) { return gstate->parent_target != NULL; } /** * _cairo_gstate_get_target: * @gstate: a #cairo_gstate_t * * Return the current drawing target; if drawing is not redirected, * this will be the same as _cairo_gstate_get_original_target(). * * Return value: the current target surface **/ cairo_surface_t * _cairo_gstate_get_target (cairo_gstate_t *gstate) { return gstate->target; } /** * _cairo_gstate_get_original_target: * @gstate: a #cairo_gstate_t * * Return the original target with which @gstate was created. This * function always returns the original target independent of any * child target that may have been set with * _cairo_gstate_redirect_target. * * Return value: the original target surface **/ cairo_surface_t * _cairo_gstate_get_original_target (cairo_gstate_t *gstate) { return gstate->original_target; } /** * _cairo_gstate_get_clip: * @gstate: a #cairo_gstate_t * * This space left intentionally blank. * * Return value: a pointer to the gstate's #cairo_clip_t structure. **/ cairo_clip_t * _cairo_gstate_get_clip (cairo_gstate_t *gstate) { return gstate->clip; } cairo_status_t _cairo_gstate_set_source (cairo_gstate_t *gstate, cairo_pattern_t *source) { if (source->status) return source->status; source = cairo_pattern_reference (source); cairo_pattern_destroy (gstate->source); gstate->source = source; gstate->source_ctm_inverse = gstate->ctm_inverse; return CAIRO_STATUS_SUCCESS; } cairo_pattern_t * _cairo_gstate_get_source (cairo_gstate_t *gstate) { if (gstate->source == &_cairo_pattern_black.base) { /* do not expose the static object to the user */ gstate->source = _cairo_pattern_create_solid (CAIRO_COLOR_BLACK); } return gstate->source; } cairo_status_t _cairo_gstate_set_operator (cairo_gstate_t *gstate, cairo_operator_t op) { gstate->op = op; return CAIRO_STATUS_SUCCESS; } cairo_operator_t _cairo_gstate_get_operator (cairo_gstate_t *gstate) { return gstate->op; } cairo_status_t _cairo_gstate_set_opacity (cairo_gstate_t *gstate, double op) { gstate->opacity = op; return CAIRO_STATUS_SUCCESS; } double _cairo_gstate_get_opacity (cairo_gstate_t *gstate) { return gstate->opacity; } cairo_status_t _cairo_gstate_set_tolerance (cairo_gstate_t *gstate, double tolerance) { gstate->tolerance = tolerance; return CAIRO_STATUS_SUCCESS; } double _cairo_gstate_get_tolerance (cairo_gstate_t *gstate) { return gstate->tolerance; } cairo_status_t _cairo_gstate_set_fill_rule (cairo_gstate_t *gstate, cairo_fill_rule_t fill_rule) { gstate->fill_rule = fill_rule; return CAIRO_STATUS_SUCCESS; } cairo_fill_rule_t _cairo_gstate_get_fill_rule (cairo_gstate_t *gstate) { return gstate->fill_rule; } cairo_status_t _cairo_gstate_set_line_width (cairo_gstate_t *gstate, double width) { gstate->stroke_style.line_width = width; return CAIRO_STATUS_SUCCESS; } double _cairo_gstate_get_line_width (cairo_gstate_t *gstate) { return gstate->stroke_style.line_width; } cairo_status_t _cairo_gstate_set_line_cap (cairo_gstate_t *gstate, cairo_line_cap_t line_cap) { gstate->stroke_style.line_cap = line_cap; return CAIRO_STATUS_SUCCESS; } cairo_line_cap_t _cairo_gstate_get_line_cap (cairo_gstate_t *gstate) { return gstate->stroke_style.line_cap; } cairo_status_t _cairo_gstate_set_line_join (cairo_gstate_t *gstate, cairo_line_join_t line_join) { gstate->stroke_style.line_join = line_join; return CAIRO_STATUS_SUCCESS; } cairo_line_join_t _cairo_gstate_get_line_join (cairo_gstate_t *gstate) { return gstate->stroke_style.line_join; } cairo_status_t _cairo_gstate_set_dash (cairo_gstate_t *gstate, const double *dash, int num_dashes, double offset) { double dash_total, on_total, off_total; int i, j; free (gstate->stroke_style.dash); gstate->stroke_style.num_dashes = num_dashes; if (gstate->stroke_style.num_dashes == 0) { gstate->stroke_style.dash = NULL; gstate->stroke_style.dash_offset = 0.0; return CAIRO_STATUS_SUCCESS; } gstate->stroke_style.dash = _cairo_malloc_ab (gstate->stroke_style.num_dashes, sizeof (double)); if (unlikely (gstate->stroke_style.dash == NULL)) { gstate->stroke_style.num_dashes = 0; return _cairo_error (CAIRO_STATUS_NO_MEMORY); } on_total = off_total = dash_total = 0.0; for (i = j = 0; i < num_dashes; i++) { if (dash[i] < 0) return _cairo_error (CAIRO_STATUS_INVALID_DASH); if (dash[i] == 0 && i > 0 && i < num_dashes - 1) { if (dash[++i] < 0) return _cairo_error (CAIRO_STATUS_INVALID_DASH); gstate->stroke_style.dash[j-1] += dash[i]; gstate->stroke_style.num_dashes -= 2; } else gstate->stroke_style.dash[j++] = dash[i]; if (dash[i]) { dash_total += dash[i]; if ((i & 1) == 0) on_total += dash[i]; else off_total += dash[i]; } } if (dash_total == 0.0) return _cairo_error (CAIRO_STATUS_INVALID_DASH); /* An odd dash value indicate symmetric repeating, so the total * is twice as long. */ if (gstate->stroke_style.num_dashes & 1) { dash_total *= 2; on_total += off_total; } if (dash_total - on_total < CAIRO_FIXED_ERROR_DOUBLE) { /* Degenerate dash -> solid line */ free (gstate->stroke_style.dash); gstate->stroke_style.dash = NULL; gstate->stroke_style.num_dashes = 0; gstate->stroke_style.dash_offset = 0.0; return CAIRO_STATUS_SUCCESS; } /* The dashing code doesn't like a negative offset or a big positive * offset, so we compute an equivalent offset which is guaranteed to be * positive and less than twice the pattern length. */ offset = fmod (offset, dash_total); if (offset < 0.0) offset += dash_total; if (offset <= 0.0) /* Take care of -0 */ offset = 0.0; gstate->stroke_style.dash_offset = offset; return CAIRO_STATUS_SUCCESS; } void _cairo_gstate_get_dash (cairo_gstate_t *gstate, double *dashes, int *num_dashes, double *offset) { if (dashes) { memcpy (dashes, gstate->stroke_style.dash, sizeof (double) * gstate->stroke_style.num_dashes); } if (num_dashes) *num_dashes = gstate->stroke_style.num_dashes; if (offset) *offset = gstate->stroke_style.dash_offset; } cairo_status_t _cairo_gstate_set_miter_limit (cairo_gstate_t *gstate, double limit) { gstate->stroke_style.miter_limit = limit; return CAIRO_STATUS_SUCCESS; } double _cairo_gstate_get_miter_limit (cairo_gstate_t *gstate) { return gstate->stroke_style.miter_limit; } void _cairo_gstate_get_matrix (cairo_gstate_t *gstate, cairo_matrix_t *matrix) { *matrix = gstate->ctm; } cairo_status_t _cairo_gstate_translate (cairo_gstate_t *gstate, double tx, double ty) { cairo_matrix_t tmp; if (! ISFINITE (tx) || ! ISFINITE (ty)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); _cairo_gstate_unset_scaled_font (gstate); cairo_matrix_init_translate (&tmp, tx, ty); cairo_matrix_multiply (&gstate->ctm, &tmp, &gstate->ctm); gstate->is_identity = FALSE; /* paranoid check against gradual numerical instability */ if (! _cairo_matrix_is_invertible (&gstate->ctm)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); cairo_matrix_init_translate (&tmp, -tx, -ty); cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp); return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_scale (cairo_gstate_t *gstate, double sx, double sy) { cairo_matrix_t tmp; if (sx * sy == 0.) /* either sx or sy is 0, or det == 0 due to underflow */ return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); if (! ISFINITE (sx) || ! ISFINITE (sy)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); _cairo_gstate_unset_scaled_font (gstate); cairo_matrix_init_scale (&tmp, sx, sy); cairo_matrix_multiply (&gstate->ctm, &tmp, &gstate->ctm); gstate->is_identity = FALSE; /* paranoid check against gradual numerical instability */ if (! _cairo_matrix_is_invertible (&gstate->ctm)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); cairo_matrix_init_scale (&tmp, 1/sx, 1/sy); cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp); return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_rotate (cairo_gstate_t *gstate, double angle) { cairo_matrix_t tmp; if (angle == 0.) return CAIRO_STATUS_SUCCESS; if (! ISFINITE (angle)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); _cairo_gstate_unset_scaled_font (gstate); cairo_matrix_init_rotate (&tmp, angle); cairo_matrix_multiply (&gstate->ctm, &tmp, &gstate->ctm); gstate->is_identity = FALSE; /* paranoid check against gradual numerical instability */ if (! _cairo_matrix_is_invertible (&gstate->ctm)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); cairo_matrix_init_rotate (&tmp, -angle); cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp); return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_transform (cairo_gstate_t *gstate, const cairo_matrix_t *matrix) { cairo_matrix_t tmp; cairo_status_t status; if (! _cairo_matrix_is_invertible (matrix)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); if (_cairo_matrix_is_identity (matrix)) return CAIRO_STATUS_SUCCESS; tmp = *matrix; status = cairo_matrix_invert (&tmp); if (unlikely (status)) return status; _cairo_gstate_unset_scaled_font (gstate); cairo_matrix_multiply (&gstate->ctm, matrix, &gstate->ctm); cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp); gstate->is_identity = FALSE; /* paranoid check against gradual numerical instability */ if (! _cairo_matrix_is_invertible (&gstate->ctm)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_set_matrix (cairo_gstate_t *gstate, const cairo_matrix_t *matrix) { cairo_status_t status; if (memcmp (matrix, &gstate->ctm, sizeof (cairo_matrix_t)) == 0) return CAIRO_STATUS_SUCCESS; if (! _cairo_matrix_is_invertible (matrix)) return _cairo_error (CAIRO_STATUS_INVALID_MATRIX); if (_cairo_matrix_is_identity (matrix)) { _cairo_gstate_identity_matrix (gstate); return CAIRO_STATUS_SUCCESS; } _cairo_gstate_unset_scaled_font (gstate); gstate->ctm = *matrix; gstate->ctm_inverse = *matrix; status = cairo_matrix_invert (&gstate->ctm_inverse); assert (status == CAIRO_STATUS_SUCCESS); gstate->is_identity = FALSE; return CAIRO_STATUS_SUCCESS; } void _cairo_gstate_identity_matrix (cairo_gstate_t *gstate) { if (_cairo_matrix_is_identity (&gstate->ctm)) return; _cairo_gstate_unset_scaled_font (gstate); cairo_matrix_init_identity (&gstate->ctm); cairo_matrix_init_identity (&gstate->ctm_inverse); gstate->is_identity = _cairo_matrix_is_identity (&gstate->target->device_transform); } void _cairo_gstate_user_to_device (cairo_gstate_t *gstate, double *x, double *y) { cairo_matrix_transform_point (&gstate->ctm, x, y); } void _cairo_gstate_user_to_device_distance (cairo_gstate_t *gstate, double *dx, double *dy) { cairo_matrix_transform_distance (&gstate->ctm, dx, dy); } void _cairo_gstate_device_to_user (cairo_gstate_t *gstate, double *x, double *y) { cairo_matrix_transform_point (&gstate->ctm_inverse, x, y); } void _cairo_gstate_device_to_user_distance (cairo_gstate_t *gstate, double *dx, double *dy) { cairo_matrix_transform_distance (&gstate->ctm_inverse, dx, dy); } void _do_cairo_gstate_user_to_backend (cairo_gstate_t *gstate, double *x, double *y) { cairo_matrix_transform_point (&gstate->ctm, x, y); cairo_matrix_transform_point (&gstate->target->device_transform, x, y); } void _do_cairo_gstate_user_to_backend_distance (cairo_gstate_t *gstate, double *x, double *y) { cairo_matrix_transform_distance (&gstate->ctm, x, y); cairo_matrix_transform_distance (&gstate->target->device_transform, x, y); } void _do_cairo_gstate_backend_to_user (cairo_gstate_t *gstate, double *x, double *y) { cairo_matrix_transform_point (&gstate->target->device_transform_inverse, x, y); cairo_matrix_transform_point (&gstate->ctm_inverse, x, y); } void _do_cairo_gstate_backend_to_user_distance (cairo_gstate_t *gstate, double *x, double *y) { cairo_matrix_transform_distance (&gstate->target->device_transform_inverse, x, y); cairo_matrix_transform_distance (&gstate->ctm_inverse, x, y); } void _cairo_gstate_backend_to_user_rectangle (cairo_gstate_t *gstate, double *x1, double *y1, double *x2, double *y2, cairo_bool_t *is_tight) { cairo_matrix_t matrix_inverse; if (! _cairo_matrix_is_identity (&gstate->target->device_transform_inverse) || ! _cairo_matrix_is_identity (&gstate->ctm_inverse)) { cairo_matrix_multiply (&matrix_inverse, &gstate->target->device_transform_inverse, &gstate->ctm_inverse); _cairo_matrix_transform_bounding_box (&matrix_inverse, x1, y1, x2, y2, is_tight); } else { if (is_tight) *is_tight = TRUE; } } /* XXX: NYI cairo_status_t _cairo_gstate_stroke_to_path (cairo_gstate_t *gstate) { cairo_status_t status; _cairo_pen_init (&gstate); return CAIRO_STATUS_SUCCESS; } */ void _cairo_gstate_path_extents (cairo_gstate_t *gstate, cairo_path_fixed_t *path, double *x1, double *y1, double *x2, double *y2) { cairo_box_t box; double px1, py1, px2, py2; if (_cairo_path_fixed_extents (path, &box)) { px1 = _cairo_fixed_to_double (box.p1.x); py1 = _cairo_fixed_to_double (box.p1.y); px2 = _cairo_fixed_to_double (box.p2.x); py2 = _cairo_fixed_to_double (box.p2.y); _cairo_gstate_backend_to_user_rectangle (gstate, &px1, &py1, &px2, &py2, NULL); } else { px1 = 0.0; py1 = 0.0; px2 = 0.0; py2 = 0.0; } if (x1) *x1 = px1; if (y1) *y1 = py1; if (x2) *x2 = px2; if (y2) *y2 = py2; } static void _cairo_gstate_copy_pattern (cairo_pattern_t *pattern, const cairo_pattern_t *original) { /* First check if the we can replace the original with a much simpler * pattern. For example, gradients that are uniform or just have a single * stop can sometimes be replaced with a solid. */ if (_cairo_pattern_is_clear (original)) { _cairo_pattern_init_solid ((cairo_solid_pattern_t *) pattern, CAIRO_COLOR_TRANSPARENT); return; } if (original->type == CAIRO_PATTERN_TYPE_LINEAR || original->type == CAIRO_PATTERN_TYPE_RADIAL) { cairo_color_t color; if (_cairo_gradient_pattern_is_solid ((cairo_gradient_pattern_t *) original, NULL, &color)) { _cairo_pattern_init_solid ((cairo_solid_pattern_t *) pattern, &color); return; } } _cairo_pattern_init_static_copy (pattern, original); } static void _cairo_gstate_copy_transformed_pattern (cairo_gstate_t *gstate, cairo_pattern_t *pattern, const cairo_pattern_t *original, const cairo_matrix_t *ctm_inverse) { _cairo_gstate_copy_pattern (pattern, original); /* apply device_transform first so that it is transformed by ctm_inverse */ if (original->type == CAIRO_PATTERN_TYPE_SURFACE) { cairo_surface_pattern_t *surface_pattern; cairo_surface_t *surface; surface_pattern = (cairo_surface_pattern_t *) original; surface = surface_pattern->surface; if (_cairo_surface_has_device_transform (surface)) _cairo_pattern_transform (pattern, &surface->device_transform); } if (! _cairo_matrix_is_identity (ctm_inverse)) _cairo_pattern_transform (pattern, ctm_inverse); if (_cairo_surface_has_device_transform (gstate->target)) { _cairo_pattern_transform (pattern, &gstate->target->device_transform_inverse); } } static void _cairo_gstate_copy_transformed_source (cairo_gstate_t *gstate, cairo_pattern_t *pattern) { _cairo_gstate_copy_transformed_pattern (gstate, pattern, gstate->source, &gstate->source_ctm_inverse); } static void _cairo_gstate_copy_transformed_mask (cairo_gstate_t *gstate, cairo_pattern_t *pattern, cairo_pattern_t *mask) { _cairo_gstate_copy_transformed_pattern (gstate, pattern, mask, &gstate->ctm_inverse); } static cairo_operator_t _reduce_op (cairo_gstate_t *gstate) { cairo_operator_t op; const cairo_pattern_t *pattern; op = gstate->op; if (op != CAIRO_OPERATOR_SOURCE) return op; pattern = gstate->source; if (pattern->type == CAIRO_PATTERN_TYPE_SOLID) { const cairo_solid_pattern_t *solid = (cairo_solid_pattern_t *) pattern; if (solid->color.alpha_short <= 0x00ff) { op = CAIRO_OPERATOR_CLEAR; } else if ((gstate->target->content & CAIRO_CONTENT_ALPHA) == 0) { if ((solid->color.red_short | solid->color.green_short | solid->color.blue_short) <= 0x00ff) { op = CAIRO_OPERATOR_CLEAR; } } } else if (pattern->type == CAIRO_PATTERN_TYPE_SURFACE) { const cairo_surface_pattern_t *surface = (cairo_surface_pattern_t *) pattern; if (surface->surface->is_clear && surface->surface->content & CAIRO_CONTENT_ALPHA) { op = CAIRO_OPERATOR_CLEAR; } } else { const cairo_gradient_pattern_t *gradient = (cairo_gradient_pattern_t *) pattern; if (gradient->n_stops == 0) op = CAIRO_OPERATOR_CLEAR; } return op; } static cairo_status_t _cairo_gstate_get_pattern_status (const cairo_pattern_t *pattern) { if (unlikely (pattern->type == CAIRO_PATTERN_TYPE_MESH && ((const cairo_mesh_pattern_t *) pattern)->current_patch)) { /* If current patch != NULL, the pattern is under construction * and cannot be used as a source */ return CAIRO_STATUS_INVALID_MESH_CONSTRUCTION; } return pattern->status; } cairo_status_t _cairo_gstate_paint (cairo_gstate_t *gstate) { cairo_pattern_union_t source_pattern; const cairo_pattern_t *pattern; cairo_status_t status; cairo_operator_t op; status = _cairo_gstate_get_pattern_status (gstate->source); if (unlikely (status)) return status; if (gstate->op == CAIRO_OPERATOR_DEST) return CAIRO_STATUS_SUCCESS; if (_cairo_clip_is_all_clipped (gstate->clip)) return CAIRO_STATUS_SUCCESS; op = _reduce_op (gstate); if (op == CAIRO_OPERATOR_CLEAR) { pattern = &_cairo_pattern_clear.base; } else { _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base); pattern = &source_pattern.base; } return _cairo_surface_paint (gstate->target, op, pattern, gstate->clip); } cairo_status_t _cairo_gstate_mask (cairo_gstate_t *gstate, cairo_pattern_t *mask) { cairo_pattern_union_t source_pattern, mask_pattern; const cairo_pattern_t *source; cairo_operator_t op; cairo_status_t status; status = _cairo_gstate_get_pattern_status (mask); if (unlikely (status)) return status; status = _cairo_gstate_get_pattern_status (gstate->source); if (unlikely (status)) return status; if (gstate->op == CAIRO_OPERATOR_DEST) return CAIRO_STATUS_SUCCESS; if (_cairo_clip_is_all_clipped (gstate->clip)) return CAIRO_STATUS_SUCCESS; assert (gstate->opacity == 1.0); if (_cairo_pattern_is_opaque (mask, NULL)) return _cairo_gstate_paint (gstate); if (_cairo_pattern_is_clear (mask) && _cairo_operator_bounded_by_mask (gstate->op)) { return CAIRO_STATUS_SUCCESS; } op = _reduce_op (gstate); if (op == CAIRO_OPERATOR_CLEAR) { source = &_cairo_pattern_clear.base; } else { _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base); source = &source_pattern.base; } _cairo_gstate_copy_transformed_mask (gstate, &mask_pattern.base, mask); if (source->type == CAIRO_PATTERN_TYPE_SOLID && mask_pattern.base.type == CAIRO_PATTERN_TYPE_SOLID && _cairo_operator_bounded_by_source (op)) { const cairo_solid_pattern_t *solid = (cairo_solid_pattern_t *) source; cairo_color_t combined; if (mask_pattern.base.has_component_alpha) { #define M(R, A, B, c) R.c = A.c * B.c M(combined, solid->color, mask_pattern.solid.color, red); M(combined, solid->color, mask_pattern.solid.color, green); M(combined, solid->color, mask_pattern.solid.color, blue); M(combined, solid->color, mask_pattern.solid.color, alpha); #undef M } else { combined = solid->color; _cairo_color_multiply_alpha (&combined, mask_pattern.solid.color.alpha); } _cairo_pattern_init_solid (&source_pattern.solid, &combined); status = _cairo_surface_paint (gstate->target, op, &source_pattern.base, gstate->clip); } else { status = _cairo_surface_mask (gstate->target, op, source, &mask_pattern.base, gstate->clip); } return status; } cairo_status_t _cairo_gstate_stroke (cairo_gstate_t *gstate, cairo_path_fixed_t *path) { cairo_pattern_union_t source_pattern; cairo_stroke_style_t style; double dash[2]; cairo_status_t status; status = _cairo_gstate_get_pattern_status (gstate->source); if (unlikely (status)) return status; if (gstate->op == CAIRO_OPERATOR_DEST) return CAIRO_STATUS_SUCCESS; if (gstate->stroke_style.line_width <= 0.0) return CAIRO_STATUS_SUCCESS; if (_cairo_clip_is_all_clipped (gstate->clip)) return CAIRO_STATUS_SUCCESS; assert (gstate->opacity == 1.0); memcpy (&style, &gstate->stroke_style, sizeof (gstate->stroke_style)); if (_cairo_stroke_style_dash_can_approximate (&gstate->stroke_style, &gstate->ctm, gstate->tolerance)) { style.dash = dash; _cairo_stroke_style_dash_approximate (&gstate->stroke_style, &gstate->ctm, gstate->tolerance, &style.dash_offset, style.dash, &style.num_dashes); } _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base); return _cairo_surface_stroke (gstate->target, gstate->op, &source_pattern.base, path, &style, &gstate->ctm, &gstate->ctm_inverse, gstate->tolerance, gstate->antialias, gstate->clip); } cairo_status_t _cairo_gstate_in_stroke (cairo_gstate_t *gstate, cairo_path_fixed_t *path, double x, double y, cairo_bool_t *inside_ret) { cairo_status_t status; cairo_rectangle_int_t extents; cairo_box_t limit; cairo_traps_t traps; if (gstate->stroke_style.line_width <= 0.0) { *inside_ret = FALSE; return CAIRO_STATUS_SUCCESS; } _cairo_gstate_user_to_backend (gstate, &x, &y); /* Before we perform the expensive stroke analysis, * check whether the point is within the extents of the path. */ _cairo_path_fixed_approximate_stroke_extents (path, &gstate->stroke_style, &gstate->ctm, &extents); if (x < extents.x || x > extents.x + extents.width || y < extents.y || y > extents.y + extents.height) { *inside_ret = FALSE; return CAIRO_STATUS_SUCCESS; } limit.p1.x = _cairo_fixed_from_double (x) - 1; limit.p1.y = _cairo_fixed_from_double (y) - 1; limit.p2.x = limit.p1.x + 2; limit.p2.y = limit.p1.y + 2; _cairo_traps_init (&traps); _cairo_traps_limit (&traps, &limit, 1); status = _cairo_path_fixed_stroke_to_traps (path, &gstate->stroke_style, &gstate->ctm, &gstate->ctm_inverse, gstate->tolerance, &traps); if (unlikely (status)) goto BAIL; *inside_ret = _cairo_traps_contain (&traps, x, y); BAIL: _cairo_traps_fini (&traps); return status; } cairo_status_t _cairo_gstate_fill (cairo_gstate_t *gstate, cairo_path_fixed_t *path) { cairo_status_t status; status = _cairo_gstate_get_pattern_status (gstate->source); if (unlikely (status)) return status; if (gstate->op == CAIRO_OPERATOR_DEST) return CAIRO_STATUS_SUCCESS; if (_cairo_clip_is_all_clipped (gstate->clip)) return CAIRO_STATUS_SUCCESS; assert (gstate->opacity == 1.0); if (_cairo_path_fixed_fill_is_empty (path)) { if (_cairo_operator_bounded_by_mask (gstate->op)) return CAIRO_STATUS_SUCCESS; status = _cairo_surface_paint (gstate->target, CAIRO_OPERATOR_CLEAR, &_cairo_pattern_clear.base, gstate->clip); } else { cairo_pattern_union_t source_pattern; const cairo_pattern_t *pattern; cairo_operator_t op; cairo_rectangle_int_t extents; cairo_box_t box; op = _reduce_op (gstate); if (op == CAIRO_OPERATOR_CLEAR) { pattern = &_cairo_pattern_clear.base; } else { _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base); pattern = &source_pattern.base; } /* Toolkits often paint the entire background with a fill */ if (_cairo_surface_get_extents (gstate->target, &extents) && _cairo_path_fixed_is_box (path, &box) && box.p1.x <= _cairo_fixed_from_int (extents.x) && box.p1.y <= _cairo_fixed_from_int (extents.y) && box.p2.x >= _cairo_fixed_from_int (extents.x + extents.width) && box.p2.y >= _cairo_fixed_from_int (extents.y + extents.height)) { status = _cairo_surface_paint (gstate->target, op, pattern, gstate->clip); } else { status = _cairo_surface_fill (gstate->target, op, pattern, path, gstate->fill_rule, gstate->tolerance, gstate->antialias, gstate->clip); } } return status; } cairo_bool_t _cairo_gstate_in_fill (cairo_gstate_t *gstate, cairo_path_fixed_t *path, double x, double y) { _cairo_gstate_user_to_backend (gstate, &x, &y); return _cairo_path_fixed_in_fill (path, gstate->fill_rule, gstate->tolerance, x, y); } cairo_bool_t _cairo_gstate_in_clip (cairo_gstate_t *gstate, double x, double y) { cairo_clip_t *clip = gstate->clip; int i; if (_cairo_clip_is_all_clipped (clip)) return FALSE; if (clip == NULL) return TRUE; _cairo_gstate_user_to_backend (gstate, &x, &y); if (x < clip->extents.x || x >= clip->extents.x + clip->extents.width || y < clip->extents.y || y >= clip->extents.y + clip->extents.height) { return FALSE; } if (clip->num_boxes) { int fx, fy; fx = _cairo_fixed_from_double (x); fy = _cairo_fixed_from_double (y); for (i = 0; i < clip->num_boxes; i++) { if (fx >= clip->boxes[i].p1.x && fx <= clip->boxes[i].p2.x && fy >= clip->boxes[i].p1.y && fy <= clip->boxes[i].p2.y) break; } if (i == clip->num_boxes) return FALSE; } if (clip->path) { cairo_clip_path_t *clip_path = clip->path; do { if (! _cairo_path_fixed_in_fill (&clip_path->path, clip_path->fill_rule, clip_path->tolerance, x, y)) return FALSE; } while ((clip_path = clip_path->prev) != NULL); } return TRUE; } cairo_status_t _cairo_gstate_copy_page (cairo_gstate_t *gstate) { cairo_surface_copy_page (gstate->target); return cairo_surface_status (gstate->target); } cairo_status_t _cairo_gstate_show_page (cairo_gstate_t *gstate) { cairo_surface_show_page (gstate->target); return cairo_surface_status (gstate->target); } static void _cairo_gstate_extents_to_user_rectangle (cairo_gstate_t *gstate, const cairo_box_t *extents, double *x1, double *y1, double *x2, double *y2) { double px1, py1, px2, py2; px1 = _cairo_fixed_to_double (extents->p1.x); py1 = _cairo_fixed_to_double (extents->p1.y); px2 = _cairo_fixed_to_double (extents->p2.x); py2 = _cairo_fixed_to_double (extents->p2.y); _cairo_gstate_backend_to_user_rectangle (gstate, &px1, &py1, &px2, &py2, NULL); if (x1) *x1 = px1; if (y1) *y1 = py1; if (x2) *x2 = px2; if (y2) *y2 = py2; } cairo_status_t _cairo_gstate_stroke_extents (cairo_gstate_t *gstate, cairo_path_fixed_t *path, double *x1, double *y1, double *x2, double *y2) { cairo_int_status_t status; cairo_box_t extents; cairo_bool_t empty; if (x1) *x1 = 0.0; if (y1) *y1 = 0.0; if (x2) *x2 = 0.0; if (y2) *y2 = 0.0; if (gstate->stroke_style.line_width <= 0.0) return CAIRO_STATUS_SUCCESS; status = CAIRO_INT_STATUS_UNSUPPORTED; if (_cairo_path_fixed_stroke_is_rectilinear (path)) { cairo_boxes_t boxes; _cairo_boxes_init (&boxes); status = _cairo_path_fixed_stroke_rectilinear_to_boxes (path, &gstate->stroke_style, &gstate->ctm, gstate->antialias, &boxes); empty = boxes.num_boxes == 0; if (! empty) _cairo_boxes_extents (&boxes, &extents); _cairo_boxes_fini (&boxes); } if (status == CAIRO_INT_STATUS_UNSUPPORTED) { cairo_traps_t traps; _cairo_traps_init (&traps); status = _cairo_path_fixed_stroke_to_traps (path, &gstate->stroke_style, &gstate->ctm, &gstate->ctm_inverse, gstate->tolerance, &traps); empty = traps.num_traps == 0; if (! empty) _cairo_traps_extents (&traps, &extents); _cairo_traps_fini (&traps); } if (! empty) { _cairo_gstate_extents_to_user_rectangle (gstate, &extents, x1, y1, x2, y2); } return status; } cairo_status_t _cairo_gstate_fill_extents (cairo_gstate_t *gstate, cairo_path_fixed_t *path, double *x1, double *y1, double *x2, double *y2) { cairo_status_t status; cairo_box_t extents; cairo_bool_t empty; if (x1) *x1 = 0.0; if (y1) *y1 = 0.0; if (x2) *x2 = 0.0; if (y2) *y2 = 0.0; if (_cairo_path_fixed_fill_is_empty (path)) return CAIRO_STATUS_SUCCESS; if (_cairo_path_fixed_fill_is_rectilinear (path)) { cairo_boxes_t boxes; _cairo_boxes_init (&boxes); status = _cairo_path_fixed_fill_rectilinear_to_boxes (path, gstate->fill_rule, gstate->antialias, &boxes); empty = boxes.num_boxes == 0; if (! empty) _cairo_boxes_extents (&boxes, &extents); _cairo_boxes_fini (&boxes); } else { cairo_traps_t traps; _cairo_traps_init (&traps); status = _cairo_path_fixed_fill_to_traps (path, gstate->fill_rule, gstate->tolerance, &traps); empty = traps.num_traps == 0; if (! empty) _cairo_traps_extents (&traps, &extents); _cairo_traps_fini (&traps); } if (! empty) { _cairo_gstate_extents_to_user_rectangle (gstate, &extents, x1, y1, x2, y2); } return status; } cairo_status_t _cairo_gstate_reset_clip (cairo_gstate_t *gstate) { _cairo_clip_destroy (gstate->clip); gstate->clip = NULL; return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_clip (cairo_gstate_t *gstate, cairo_path_fixed_t *path) { gstate->clip = _cairo_clip_intersect_path (gstate->clip, path, gstate->fill_rule, gstate->tolerance, gstate->antialias); /* XXX */ return CAIRO_STATUS_SUCCESS; } static cairo_bool_t _cairo_gstate_int_clip_extents (cairo_gstate_t *gstate, cairo_rectangle_int_t *extents) { cairo_bool_t is_bounded; is_bounded = _cairo_surface_get_extents (gstate->target, extents); if (gstate->clip) { _cairo_rectangle_intersect (extents, _cairo_clip_get_extents (gstate->clip)); is_bounded = TRUE; } return is_bounded; } cairo_bool_t _cairo_gstate_clip_extents (cairo_gstate_t *gstate, double *x1, double *y1, double *x2, double *y2) { cairo_rectangle_int_t extents; double px1, py1, px2, py2; if (! _cairo_gstate_int_clip_extents (gstate, &extents)) return FALSE; px1 = extents.x; py1 = extents.y; px2 = extents.x + (int) extents.width; py2 = extents.y + (int) extents.height; _cairo_gstate_backend_to_user_rectangle (gstate, &px1, &py1, &px2, &py2, NULL); if (x1) *x1 = px1; if (y1) *y1 = py1; if (x2) *x2 = px2; if (y2) *y2 = py2; return TRUE; } cairo_rectangle_list_t* _cairo_gstate_copy_clip_rectangle_list (cairo_gstate_t *gstate) { cairo_rectangle_int_t extents; cairo_rectangle_list_t *list; cairo_clip_t *clip; if (_cairo_surface_get_extents (gstate->target, &extents)) clip = _cairo_clip_copy_intersect_rectangle (gstate->clip, &extents); else clip = gstate->clip; list = _cairo_clip_copy_rectangle_list (clip, gstate); if (clip != gstate->clip) _cairo_clip_destroy (clip); return list; } static void _cairo_gstate_unset_scaled_font (cairo_gstate_t *gstate) { if (gstate->scaled_font == NULL) return; if (gstate->previous_scaled_font != NULL) cairo_scaled_font_destroy (gstate->previous_scaled_font); gstate->previous_scaled_font = gstate->scaled_font; gstate->scaled_font = NULL; } cairo_status_t _cairo_gstate_set_font_size (cairo_gstate_t *gstate, double size) { _cairo_gstate_unset_scaled_font (gstate); cairo_matrix_init_scale (&gstate->font_matrix, size, size); return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_set_font_matrix (cairo_gstate_t *gstate, const cairo_matrix_t *matrix) { if (memcmp (matrix, &gstate->font_matrix, sizeof (cairo_matrix_t)) == 0) return CAIRO_STATUS_SUCCESS; _cairo_gstate_unset_scaled_font (gstate); gstate->font_matrix = *matrix; return CAIRO_STATUS_SUCCESS; } void _cairo_gstate_get_font_matrix (cairo_gstate_t *gstate, cairo_matrix_t *matrix) { *matrix = gstate->font_matrix; } void _cairo_gstate_set_font_options (cairo_gstate_t *gstate, const cairo_font_options_t *options) { if (memcmp (options, &gstate->font_options, sizeof (cairo_font_options_t)) == 0) return; _cairo_gstate_unset_scaled_font (gstate); _cairo_font_options_init_copy (&gstate->font_options, options); } void _cairo_gstate_get_font_options (cairo_gstate_t *gstate, cairo_font_options_t *options) { *options = gstate->font_options; } cairo_status_t _cairo_gstate_get_font_face (cairo_gstate_t *gstate, cairo_font_face_t **font_face) { cairo_status_t status; status = _cairo_gstate_ensure_font_face (gstate); if (unlikely (status)) return status; *font_face = gstate->font_face; return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_get_scaled_font (cairo_gstate_t *gstate, cairo_scaled_font_t **scaled_font) { cairo_status_t status; status = _cairo_gstate_ensure_scaled_font (gstate); if (unlikely (status)) return status; *scaled_font = gstate->scaled_font; return CAIRO_STATUS_SUCCESS; } /* * Like everything else in this file, fonts involve Too Many Coordinate Spaces; * it is easy to get confused about what's going on. * * The user's view * --------------- * * Users ask for things in user space. When cairo starts, a user space unit * is about 1/96 inch, which is similar to (but importantly different from) * the normal "point" units most users think in terms of. When a user * selects a font, its scale is set to "one user unit". The user can then * independently scale the user coordinate system *or* the font matrix, in * order to adjust the rendered size of the font. * * Metrics are returned in user space, whether they are obtained from * the currently selected font in a #cairo_t or from a #cairo_scaled_font_t * which is a font specialized to a particular scale matrix, CTM, and target * surface. * * The font's view * --------------- * * Fonts are designed and stored (in say .ttf files) in "font space", which * describes an "EM Square" (a design tile) and has some abstract number * such as 1000, 1024, or 2048 units per "EM". This is basically an * uninteresting space for us, but we need to remember that it exists. * * Font resources (from libraries or operating systems) render themselves * to a particular device. Since they do not want to make most programmers * worry about the font design space, the scaling API is simplified to * involve just telling the font the required pixel size of the EM square * (that is, in device space). * * * Cairo's gstate view * ------------------- * * In addition to the CTM and CTM inverse, we keep a matrix in the gstate * called the "font matrix" which describes the user's most recent * font-scaling or font-transforming request. This is kept in terms of an * abstract scale factor, composed with the CTM and used to set the font's * pixel size. So if the user asks to "scale the font by 12", the matrix * is: * * [ 12.0, 0.0, 0.0, 12.0, 0.0, 0.0 ] * * It is an affine matrix, like all cairo matrices, where its tx and ty * components are used to "nudging" fonts around and are handled in gstate * and then ignored by the "scaled-font" layer. * * In order to perform any action on a font, we must build an object * called a #cairo_font_scale_t; this contains the central 2x2 matrix * resulting from "font matrix * CTM" (sans the font matrix translation * components as stated in the previous paragraph). * * We pass this to the font when making requests of it, which causes it to * reply for a particular [user request, device] combination, under the CTM * (to accommodate the "zoom in" == "bigger fonts" issue above). * * The other terms in our communication with the font are therefore in * device space. When we ask it to perform text->glyph conversion, it will * produce a glyph string in device space. Glyph vectors we pass to it for * measuring or rendering should be in device space. The metrics which we * get back from the font will be in device space. The contents of the * global glyph image cache will be in device space. * * * Cairo's public view * ------------------- * * Since the values entering and leaving via public API calls are in user * space, the gstate functions typically need to multiply arguments by the * CTM (for user-input glyph vectors), and return values by the CTM inverse * (for font responses such as metrics or glyph vectors). * */ static cairo_status_t _cairo_gstate_ensure_font_face (cairo_gstate_t *gstate) { cairo_font_face_t *font_face; if (gstate->font_face != NULL) return gstate->font_face->status; font_face = cairo_toy_font_face_create (CAIRO_FONT_FAMILY_DEFAULT, CAIRO_FONT_SLANT_DEFAULT, CAIRO_FONT_WEIGHT_DEFAULT); if (font_face->status) return font_face->status; gstate->font_face = font_face; return CAIRO_STATUS_SUCCESS; } static cairo_status_t _cairo_gstate_ensure_scaled_font (cairo_gstate_t *gstate) { cairo_status_t status; cairo_font_options_t options; cairo_scaled_font_t *scaled_font; if (gstate->scaled_font != NULL) return gstate->scaled_font->status; status = _cairo_gstate_ensure_font_face (gstate); if (unlikely (status)) return status; cairo_surface_get_font_options (gstate->target, &options); cairo_font_options_merge (&options, &gstate->font_options); scaled_font = cairo_scaled_font_create (gstate->font_face, &gstate->font_matrix, &gstate->ctm, &options); status = cairo_scaled_font_status (scaled_font); if (unlikely (status)) return status; gstate->scaled_font = scaled_font; return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_get_font_extents (cairo_gstate_t *gstate, cairo_font_extents_t *extents) { cairo_status_t status = _cairo_gstate_ensure_scaled_font (gstate); if (unlikely (status)) return status; cairo_scaled_font_extents (gstate->scaled_font, extents); return cairo_scaled_font_status (gstate->scaled_font); } cairo_status_t _cairo_gstate_set_font_face (cairo_gstate_t *gstate, cairo_font_face_t *font_face) { if (font_face && font_face->status) return _cairo_error (font_face->status); if (font_face == gstate->font_face) return CAIRO_STATUS_SUCCESS; cairo_font_face_destroy (gstate->font_face); gstate->font_face = cairo_font_face_reference (font_face); _cairo_gstate_unset_scaled_font (gstate); return CAIRO_STATUS_SUCCESS; } cairo_status_t _cairo_gstate_glyph_extents (cairo_gstate_t *gstate, const cairo_glyph_t *glyphs, int num_glyphs, cairo_text_extents_t *extents) { cairo_status_t status; status = _cairo_gstate_ensure_scaled_font (gstate); if (unlikely (status)) return status; cairo_scaled_font_glyph_extents (gstate->scaled_font, glyphs, num_glyphs, extents); return cairo_scaled_font_status (gstate->scaled_font); } cairo_status_t _cairo_gstate_show_text_glyphs (cairo_gstate_t *gstate, const cairo_glyph_t *glyphs, int num_glyphs, cairo_glyph_text_info_t *info) { cairo_glyph_t stack_transformed_glyphs[CAIRO_STACK_ARRAY_LENGTH (cairo_glyph_t)]; cairo_text_cluster_t stack_transformed_clusters[CAIRO_STACK_ARRAY_LENGTH (cairo_text_cluster_t)]; cairo_pattern_union_t source_pattern; cairo_glyph_t *transformed_glyphs; const cairo_pattern_t *pattern; cairo_text_cluster_t *transformed_clusters; cairo_operator_t op; cairo_status_t status; status = _cairo_gstate_get_pattern_status (gstate->source); if (unlikely (status)) return status; if (gstate->op == CAIRO_OPERATOR_DEST) return CAIRO_STATUS_SUCCESS; if (_cairo_clip_is_all_clipped (gstate->clip)) return CAIRO_STATUS_SUCCESS; status = _cairo_gstate_ensure_scaled_font (gstate); if (unlikely (status)) return status; transformed_glyphs = stack_transformed_glyphs; transformed_clusters = stack_transformed_clusters; if (num_glyphs > ARRAY_LENGTH (stack_transformed_glyphs)) { transformed_glyphs = cairo_glyph_allocate (num_glyphs); if (unlikely (transformed_glyphs == NULL)) return _cairo_error (CAIRO_STATUS_NO_MEMORY); } if (info != NULL) { if (info->num_clusters > ARRAY_LENGTH (stack_transformed_clusters)) { transformed_clusters = cairo_text_cluster_allocate (info->num_clusters); if (unlikely (transformed_clusters == NULL)) { status = _cairo_error (CAIRO_STATUS_NO_MEMORY); goto CLEANUP_GLYPHS; } } _cairo_gstate_transform_glyphs_to_backend (gstate, glyphs, num_glyphs, info->clusters, info->num_clusters, info->cluster_flags, transformed_glyphs, &num_glyphs, transformed_clusters); } else { _cairo_gstate_transform_glyphs_to_backend (gstate, glyphs, num_glyphs, NULL, 0, 0, transformed_glyphs, &num_glyphs, NULL); } if (num_glyphs == 0) goto CLEANUP_GLYPHS; op = _reduce_op (gstate); if (op == CAIRO_OPERATOR_CLEAR) { pattern = &_cairo_pattern_clear.base; } else { _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base); pattern = &source_pattern.base; } /* For really huge font sizes, we can just do path;fill instead of * show_glyphs, as show_glyphs would put excess pressure on the cache, * and moreover, not all components below us correctly handle huge font * sizes. I wanted to set the limit at 256. But alas, seems like cairo's * rasterizer is something like ten times slower than freetype's for huge * sizes. So, no win just yet. For now, do it for insanely-huge sizes, * just to make sure we don't make anyone unhappy. When we get a really * fast rasterizer in cairo, we may want to readjust this. * * Needless to say, do this only if show_text_glyphs is not available. */ if (cairo_surface_has_show_text_glyphs (gstate->target) || _cairo_scaled_font_get_max_scale (gstate->scaled_font) <= 10240) { if (info != NULL) { status = _cairo_surface_show_text_glyphs (gstate->target, op, pattern, info->utf8, info->utf8_len, transformed_glyphs, num_glyphs, transformed_clusters, info->num_clusters, info->cluster_flags, gstate->scaled_font, gstate->clip); } else { status = _cairo_surface_show_text_glyphs (gstate->target, op, pattern, NULL, 0, transformed_glyphs, num_glyphs, NULL, 0, 0, gstate->scaled_font, gstate->clip); } } else { cairo_path_fixed_t path; _cairo_path_fixed_init (&path); status = _cairo_scaled_font_glyph_path (gstate->scaled_font, transformed_glyphs, num_glyphs, &path); if (status == CAIRO_STATUS_SUCCESS) { status = _cairo_surface_fill (gstate->target, op, pattern, &path, CAIRO_FILL_RULE_WINDING, gstate->tolerance, gstate->scaled_font->options.antialias, gstate->clip); } _cairo_path_fixed_fini (&path); } CLEANUP_GLYPHS: if (transformed_glyphs != stack_transformed_glyphs) cairo_glyph_free (transformed_glyphs); if (transformed_clusters != stack_transformed_clusters) cairo_text_cluster_free (transformed_clusters); return status; } cairo_status_t _cairo_gstate_glyph_path (cairo_gstate_t *gstate, const cairo_glyph_t *glyphs, int num_glyphs, cairo_path_fixed_t *path) { cairo_glyph_t stack_transformed_glyphs[CAIRO_STACK_ARRAY_LENGTH (cairo_glyph_t)]; cairo_glyph_t *transformed_glyphs; cairo_status_t status; status = _cairo_gstate_ensure_scaled_font (gstate); if (unlikely (status)) return status; if (num_glyphs < ARRAY_LENGTH (stack_transformed_glyphs)) { transformed_glyphs = stack_transformed_glyphs; } else { transformed_glyphs = cairo_glyph_allocate (num_glyphs); if (unlikely (transformed_glyphs == NULL)) return _cairo_error (CAIRO_STATUS_NO_MEMORY); } _cairo_gstate_transform_glyphs_to_backend (gstate, glyphs, num_glyphs, NULL, 0, 0, transformed_glyphs, &num_glyphs, NULL); status = _cairo_scaled_font_glyph_path (gstate->scaled_font, transformed_glyphs, num_glyphs, path); if (transformed_glyphs != stack_transformed_glyphs) cairo_glyph_free (transformed_glyphs); return status; } cairo_status_t _cairo_gstate_set_antialias (cairo_gstate_t *gstate, cairo_antialias_t antialias) { gstate->antialias = antialias; return CAIRO_STATUS_SUCCESS; } cairo_antialias_t _cairo_gstate_get_antialias (cairo_gstate_t *gstate) { return gstate->antialias; } /** * _cairo_gstate_transform_glyphs_to_backend: * @gstate: a #cairo_gstate_t * @glyphs: the array of #cairo_glyph_t objects to be transformed * @num_glyphs: the number of elements in @glyphs * @transformed_glyphs: a pre-allocated array of at least @num_glyphs * #cairo_glyph_t objects * @num_transformed_glyphs: the number of elements in @transformed_glyphs * after dropping out of bounds glyphs, or %NULL if glyphs shouldn't be * dropped * * Transform an array of glyphs to backend space by first adding the offset * of the font matrix, then transforming from user space to backend space. * The result of the transformation is placed in @transformed_glyphs. * * This also uses information from the scaled font and the surface to * cull/drop glyphs that will not be visible. **/ static void _cairo_gstate_transform_glyphs_to_backend (cairo_gstate_t *gstate, const cairo_glyph_t *glyphs, int num_glyphs, const cairo_text_cluster_t *clusters, int num_clusters, cairo_text_cluster_flags_t cluster_flags, cairo_glyph_t *transformed_glyphs, int *num_transformed_glyphs, cairo_text_cluster_t *transformed_clusters) { cairo_rectangle_int_t surface_extents; cairo_matrix_t *ctm = &gstate->ctm; cairo_matrix_t *font_matrix = &gstate->font_matrix; cairo_matrix_t *device_transform = &gstate->target->device_transform; cairo_bool_t drop = FALSE; double x1 = 0, x2 = 0, y1 = 0, y2 = 0; int i, j, k; drop = TRUE; if (! _cairo_gstate_int_clip_extents (gstate, &surface_extents)) { drop = FALSE; /* unbounded surface */ } else { double scale10 = 10 * _cairo_scaled_font_get_max_scale (gstate->scaled_font); if (surface_extents.width == 0 || surface_extents.height == 0) { /* No visible area. Don't draw anything */ *num_transformed_glyphs = 0; return; } /* XXX We currently drop any glyphs that has its position outside * of the surface boundaries by a safety margin depending on the * font scale. This however can fail in extreme cases where the * font has really long swashes for example... We can correctly * handle that by looking the glyph up and using its device bbox * to device if it's going to be visible, but I'm not inclined to * do that now. */ x1 = surface_extents.x - scale10; y1 = surface_extents.y - scale10; x2 = surface_extents.x + (int) surface_extents.width + scale10; y2 = surface_extents.y + (int) surface_extents.height + scale10; } if (!drop) *num_transformed_glyphs = num_glyphs; #define KEEP_GLYPH(glyph) (x1 <= glyph.x && glyph.x <= x2 && y1 <= glyph.y && glyph.y <= y2) j = 0; if (_cairo_matrix_is_identity (ctm) && _cairo_matrix_is_identity (device_transform) && font_matrix->x0 == 0 && font_matrix->y0 == 0) { if (! drop) { memcpy (transformed_glyphs, glyphs, num_glyphs * sizeof (cairo_glyph_t)); memcpy (transformed_clusters, clusters, num_clusters * sizeof (cairo_text_cluster_t)); j = num_glyphs; } else if (num_clusters == 0) { for (i = 0; i < num_glyphs; i++) { transformed_glyphs[j].index = glyphs[i].index; transformed_glyphs[j].x = glyphs[i].x; transformed_glyphs[j].y = glyphs[i].y; if (KEEP_GLYPH (transformed_glyphs[j])) j++; } } else { const cairo_glyph_t *cur_glyph; if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) cur_glyph = glyphs + num_glyphs - 1; else cur_glyph = glyphs; for (i = 0; i < num_clusters; i++) { cairo_bool_t cluster_visible = FALSE; for (k = 0; k < clusters[i].num_glyphs; k++) { transformed_glyphs[j+k].index = cur_glyph->index; transformed_glyphs[j+k].x = cur_glyph->x; transformed_glyphs[j+k].y = cur_glyph->y; if (KEEP_GLYPH (transformed_glyphs[j+k])) cluster_visible = TRUE; if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) cur_glyph--; else cur_glyph++; } transformed_clusters[i] = clusters[i]; if (cluster_visible) j += k; else transformed_clusters[i].num_glyphs = 0; } } } else if (_cairo_matrix_is_translation (ctm) && _cairo_matrix_is_translation (device_transform)) { double tx = font_matrix->x0 + ctm->x0 + device_transform->x0; double ty = font_matrix->y0 + ctm->y0 + device_transform->y0; if (! drop || num_clusters == 0) { for (i = 0; i < num_glyphs; i++) { transformed_glyphs[j].index = glyphs[i].index; transformed_glyphs[j].x = glyphs[i].x + tx; transformed_glyphs[j].y = glyphs[i].y + ty; if (!drop || KEEP_GLYPH (transformed_glyphs[j])) j++; } memcpy (transformed_clusters, clusters, num_clusters * sizeof (cairo_text_cluster_t)); } else { const cairo_glyph_t *cur_glyph; if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) cur_glyph = glyphs + num_glyphs - 1; else cur_glyph = glyphs; for (i = 0; i < num_clusters; i++) { cairo_bool_t cluster_visible = FALSE; for (k = 0; k < clusters[i].num_glyphs; k++) { transformed_glyphs[j+k].index = cur_glyph->index; transformed_glyphs[j+k].x = cur_glyph->x + tx; transformed_glyphs[j+k].y = cur_glyph->y + ty; if (KEEP_GLYPH (transformed_glyphs[j+k])) cluster_visible = TRUE; if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) cur_glyph--; else cur_glyph++; } transformed_clusters[i] = clusters[i]; if (cluster_visible) j += k; else transformed_clusters[i].num_glyphs = 0; } } } else { cairo_matrix_t aggregate_transform; cairo_matrix_init_translate (&aggregate_transform, gstate->font_matrix.x0, gstate->font_matrix.y0); cairo_matrix_multiply (&aggregate_transform, &aggregate_transform, ctm); cairo_matrix_multiply (&aggregate_transform, &aggregate_transform, device_transform); if (! drop || num_clusters == 0) { for (i = 0; i < num_glyphs; i++) { transformed_glyphs[j] = glyphs[i]; cairo_matrix_transform_point (&aggregate_transform, &transformed_glyphs[j].x, &transformed_glyphs[j].y); if (! drop || KEEP_GLYPH (transformed_glyphs[j])) j++; } memcpy (transformed_clusters, clusters, num_clusters * sizeof (cairo_text_cluster_t)); } else { const cairo_glyph_t *cur_glyph; if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) cur_glyph = glyphs + num_glyphs - 1; else cur_glyph = glyphs; for (i = 0; i < num_clusters; i++) { cairo_bool_t cluster_visible = FALSE; for (k = 0; k < clusters[i].num_glyphs; k++) { transformed_glyphs[j+k] = *cur_glyph; cairo_matrix_transform_point (&aggregate_transform, &transformed_glyphs[j+k].x, &transformed_glyphs[j+k].y); if (KEEP_GLYPH (transformed_glyphs[j+k])) cluster_visible = TRUE; if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) cur_glyph--; else cur_glyph++; } transformed_clusters[i] = clusters[i]; if (cluster_visible) j += k; else transformed_clusters[i].num_glyphs = 0; } } } *num_transformed_glyphs = j; if (num_clusters != 0 && cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) { for (i = 0; i < --j; i++) { cairo_glyph_t tmp; tmp = transformed_glyphs[i]; transformed_glyphs[i] = transformed_glyphs[j]; transformed_glyphs[j] = tmp; } } }