/* Pango * pangocairo-fontmap.c: Cairo font handling * * Copyright (C) 2000-2005 Red Hat Software * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #include #include "pangocairo.h" #include "pangocairo-private.h" #include "pango-impl-utils.h" #include typedef struct _PangoCairoContextInfo PangoCairoContextInfo; struct _PangoCairoContextInfo { double dpi; cairo_font_options_t *set_options; cairo_font_options_t *surface_options; cairo_font_options_t *merged_options; PangoCairoShapeRendererFunc shape_renderer_func; gpointer shape_renderer_data; GDestroyNotify shape_renderer_notify; }; static void free_context_info (PangoCairoContextInfo *info) { if (info->set_options) cairo_font_options_destroy (info->set_options); if (info->surface_options) cairo_font_options_destroy (info->surface_options); if (info->merged_options) cairo_font_options_destroy (info->merged_options); if (info->shape_renderer_notify) info->shape_renderer_notify (info->shape_renderer_data); g_slice_free (PangoCairoContextInfo, info); } static PangoCairoContextInfo * get_context_info (PangoContext *context, gboolean create) { static GQuark context_info_quark; PangoCairoContextInfo *info; if (G_UNLIKELY (!context_info_quark)) context_info_quark = g_quark_from_static_string ("pango-cairo-context-info"); info = g_object_get_qdata (G_OBJECT (context), context_info_quark); if (G_UNLIKELY (!info) && create) { info = g_slice_new0 (PangoCairoContextInfo); info->dpi = -1.0; g_object_set_qdata_full (G_OBJECT (context), context_info_quark, info, (GDestroyNotify)free_context_info); } return info; } static gboolean _pango_cairo_update_context (cairo_t *cr, PangoContext *context) { PangoCairoContextInfo *info; cairo_matrix_t cairo_matrix; cairo_surface_t *target; PangoMatrix pango_matrix; const PangoMatrix *current_matrix, identity_matrix = PANGO_MATRIX_INIT; const cairo_font_options_t *merged_options; gboolean changed = FALSE; info = get_context_info (context, TRUE); target = cairo_get_target (cr); if (!info->surface_options) { info->surface_options = cairo_font_options_create (); changed = TRUE; cairo_surface_get_font_options (target, info->surface_options); } else { cairo_font_options_t *surface_options = cairo_font_options_create (); cairo_surface_get_font_options (target, surface_options); if (!cairo_font_options_equal (surface_options, info->surface_options)) { cairo_surface_get_font_options (target, info->surface_options); changed = TRUE; } cairo_font_options_destroy (surface_options); } if (info->merged_options) { cairo_font_options_destroy (info->merged_options); info->merged_options = NULL; } merged_options = _pango_cairo_context_get_merged_font_options (context); cairo_get_matrix (cr, &cairo_matrix); pango_matrix.xx = cairo_matrix.xx; pango_matrix.yx = cairo_matrix.yx; pango_matrix.xy = cairo_matrix.xy; pango_matrix.yy = cairo_matrix.yy; pango_matrix.x0 = cairo_matrix.x0; pango_matrix.y0 = cairo_matrix.y0; current_matrix = pango_context_get_matrix (context); if (!current_matrix) current_matrix = &identity_matrix; /* layout is matrix-independent if metrics-hinting is off. * also ignore matrix translation offsets */ if ((cairo_font_options_get_hint_metrics (merged_options) != CAIRO_HINT_METRICS_OFF) && (0 != memcmp (&pango_matrix, current_matrix, 4 * sizeof (double)))) changed = TRUE; pango_context_set_matrix (context, &pango_matrix); return changed; } /** * pango_cairo_update_context: * @cr: a Cairo context * @context: a #PangoContext, from pango_cairo_font_map_create_context() * * Updates a #PangoContext previously created for use with Cairo to * match the current transformation and target surface of a Cairo * context. If any layouts have been created for the context, * it's necessary to call pango_layout_context_changed() on those * layouts. * * Since: 1.10 **/ void pango_cairo_update_context (cairo_t *cr, PangoContext *context) { g_return_if_fail (cr != NULL); g_return_if_fail (PANGO_IS_CONTEXT (context)); (void) _pango_cairo_update_context (cr, context); } /** * pango_cairo_context_set_resolution: * @context: a #PangoContext, from pango_cairo_font_map_create_context() * @dpi: the resolution in "dots per inch". (Physical inches aren't actually * involved; the terminology is conventional.) A 0 or negative value * means to use the resolution from the font map. * * Sets the resolution for the context. This is a scale factor between * points specified in a #PangoFontDescription and Cairo units. The * default value is 96, meaning that a 10 point font will be 13 * units high. (10 * 96. / 72. = 13.3). * * Since: 1.10 **/ void pango_cairo_context_set_resolution (PangoContext *context, double dpi) { PangoCairoContextInfo *info = get_context_info (context, TRUE); info->dpi = dpi; } /** * pango_cairo_context_get_resolution: * @context: a #PangoContext, from pango_cairo_font_map_create_context() * * Gets the resolution for the context. See pango_cairo_context_set_resolution() * * Return value: the resolution in "dots per inch". A negative value will * be returned if no resolution has previously been set. * * Since: 1.10 **/ double pango_cairo_context_get_resolution (PangoContext *context) { PangoCairoContextInfo *info = get_context_info (context, FALSE); if (info) return info->dpi; else return -1.0; } /** * pango_cairo_context_set_font_options: * @context: a #PangoContext, from pango_cairo_font_map_create_context() * @options: a #cairo_font_options_t, or %NULL to unset any previously set * options. A copy is made. * * Sets the font options used when rendering text with this context. * These options override any options that pango_cairo_update_context() * derives from the target surface. * * Since: 1.10 */ void pango_cairo_context_set_font_options (PangoContext *context, const cairo_font_options_t *options) { PangoCairoContextInfo *info; g_return_if_fail (PANGO_IS_CONTEXT (context)); info = get_context_info (context, TRUE); if (info->set_options) cairo_font_options_destroy (info->set_options); if (options) info->set_options = cairo_font_options_copy (options); else info->set_options = NULL; if (info->merged_options) { cairo_font_options_destroy (info->merged_options); info->merged_options = NULL; } } /** * pango_cairo_context_get_font_options: * @context: a #PangoContext, from pango_cairo_font_map_create_context() * * Retrieves any font rendering options previously set with * pango_cairo_font_map_set_font_options(). This functions not report options * that are derived from the target surface by pango_cairo_update_context() * * Return value: the font options previously set on the context, or %NULL * if no options have been set. This value is owned by the context * and must not be modified or freed. * * Since: 1.10 **/ G_CONST_RETURN cairo_font_options_t * pango_cairo_context_get_font_options (PangoContext *context) { PangoCairoContextInfo *info; g_return_val_if_fail (PANGO_IS_CONTEXT (context), NULL); info = get_context_info (context, FALSE); if (info) return info->set_options; else return NULL; } /** * _pango_cairo_context_merge_font_options: * @context: a #PangoContext * @options: a #cairo_font_options_t * * Merge together options from the target surface and explicitly set * on the context. * * Return value: the combined set of font options. This value is owned * by the context and must not be modified or freed. **/ G_CONST_RETURN cairo_font_options_t * _pango_cairo_context_get_merged_font_options (PangoContext *context) { PangoCairoContextInfo *info = get_context_info (context, TRUE); if (!info->merged_options) { info->merged_options = cairo_font_options_create (); if (info->surface_options) cairo_font_options_merge (info->merged_options, info->surface_options); if (info->set_options) cairo_font_options_merge (info->merged_options, info->set_options); } return info->merged_options; } /** * pango_cairo_context_set_shape_renderer: * @context: a #PangoContext, from pango_cairo_font_map_create_context() * @func: Callback function for rendering attributes of type * %PANGO_ATTR_SHAPE, or %NULL to disable shape rendering. * @data: User data that will be passed to @func. * @dnotify: Callback that will be called when the * context is freed to release @data, or %NULL. * * Sets callback function for context to use for rendering attributes * of type %PANGO_ATTR_SHAPE. See #PangoCairoShapeRendererFunc for * details. * * Since: 1.18 */ void pango_cairo_context_set_shape_renderer (PangoContext *context, PangoCairoShapeRendererFunc func, gpointer data, GDestroyNotify dnotify) { PangoCairoContextInfo *info; g_return_if_fail (PANGO_IS_CONTEXT (context)); info = get_context_info (context, TRUE); if (info->shape_renderer_notify) info->shape_renderer_notify (info->shape_renderer_data); info->shape_renderer_func = func; info->shape_renderer_data = data; info->shape_renderer_notify = dnotify; } /** * pango_cairo_context_get_shape_renderer: * @context: a #PangoContext, from pango_cairo_font_map_create_context() * @data: Pointer to #gpointer to return user data * * Sets callback function for context to use for rendering attributes * of type %PANGO_ATTR_SHAPE. See #PangoCairoShapeRendererFunc for * details. * * Retrieves callback function and associated user data for rendering * attributes of type %PANGO_ATTR_SHAPE as set by * pango_cairo_context_set_shape_renderer(), if any. * * Return value: the shape rendering callback previously set on the context, or %NULL * if no shape rendering callback have been set. * * Since: 1.18 */ PangoCairoShapeRendererFunc pango_cairo_context_get_shape_renderer (PangoContext *context, gpointer *data) { PangoCairoContextInfo *info; g_return_val_if_fail (PANGO_IS_CONTEXT (context), NULL); info = get_context_info (context, FALSE); if (info) { if (data) *data = info->shape_renderer_data; return info->shape_renderer_func; } else { if (data) *data = NULL; return NULL; } } /** * pango_cairo_create_layout: * @cr: a Cairo context * * Creates a layout object set up to match the current transformation * and target surface of the Cairo context. This layout can then be * used for text measurement with functions like * pango_layout_get_size() or drawing with functions like * pango_cairo_show_layout(). If you change the transformation * or target surface for @cr, you need to call pango_cairo_update_layout() * * This function is the most convenient way to use Cairo with Pango, * however it is slightly inefficient since it creates a separate * #PangoContext object for each layout. This might matter in an * application that was laying out large amounts of text. * * Return value: the newly created #PangoLayout. Free with * g_object_unref(). * * Since: 1.10 **/ PangoLayout * pango_cairo_create_layout (cairo_t *cr) { PangoFontMap *fontmap; PangoContext *context; PangoLayout *layout; g_return_val_if_fail (cr != NULL, NULL); fontmap = pango_cairo_font_map_get_default (); context = pango_cairo_font_map_create_context ((PangoCairoFontMap *) (fontmap)); layout = pango_layout_new (context); pango_cairo_update_context (cr, context); g_object_unref (context); return layout; } /** * pango_cairo_update_layout: * @cr: a Cairo context * @layout: a #PangoLayout, from pango_cairo_create_layout() * * Updates the private #PangoContext of a #PangoLayout created with * pango_cairo_create_layout() to match the current transformation * and target surface of a Cairo context. * * Since: 1.10 **/ void pango_cairo_update_layout (cairo_t *cr, PangoLayout *layout) { g_return_if_fail (cr != NULL); g_return_if_fail (PANGO_IS_LAYOUT (layout)); if (_pango_cairo_update_context (cr, pango_layout_get_context (layout))) pango_layout_context_changed (layout); }
