Add new cairo_user_scaled_font_get_foreground_source() function

The previous approach using foreground colors in user fonts does not
work for gradients since the foreground color is not available at the
time of recording.

Add a new function cairo_user_scaled_font_get_foreground_source() that
can be called by the color render function to retrieve the foreground
pattern. Calling this function signals to cairo that the foreground
color is used. In this case cairo will call the render function
whenever the foreground color has changed.

1 files changed, 48 insertions, 14 deletions

diff --git a/src/cairo-scaled-font.c b/src/cairo-scaled-font.c
index cc52ed577..d7e3f1e4b 100755
--- a/src/cairo-scaled-font.c
+++ b/src/cairo-scaled-font.c
@@ -2653,10 +2653,19 @@ _cairo_scaled_glyph_set_path (cairo_scaled_glyph_t *scaled_glyph,
 	scaled_glyph->has_info &= ~CAIRO_SCALED_GLYPH_INFO_PATH;
 }
 
+/**
+ * _cairo_scaled_glyph_set_recording_surface:
+ * @scaled_glyph: a #cairo_scaled_glyph_t
+ * @scaled_font: a #cairo_scaled_font_t
+ * @recording_surface: The recording surface
+ * @foreground_color: The foreground color that was used to record the
+ * glyph, or NULL if foreground color not required.
+ */
 void
 _cairo_scaled_glyph_set_recording_surface (cairo_scaled_glyph_t *scaled_glyph,
-					   cairo_scaled_font_t *scaled_font,
-					   cairo_surface_t *recording_surface)
+					   cairo_scaled_font_t  *scaled_font,
+					   cairo_surface_t      *recording_surface,
+					   const cairo_color_t * foreground_color)
 {
     if (scaled_glyph->recording_surface != NULL) {
 	cairo_surface_finish (scaled_glyph->recording_surface);
@@ -2664,6 +2673,9 @@ _cairo_scaled_glyph_set_recording_surface (cairo_scaled_glyph_t *scaled_glyph,
     }
 
     scaled_glyph->recording_surface = recording_surface;
+    scaled_glyph->recording_uses_foreground_color = foreground_color != NULL;
+    if (foreground_color)
+	scaled_glyph->foreground_color = *foreground_color;
 
     if (recording_surface != NULL)
 	scaled_glyph->has_info |= CAIRO_SCALED_GLYPH_INFO_RECORDING_SURFACE;
@@ -2671,11 +2683,19 @@ _cairo_scaled_glyph_set_recording_surface (cairo_scaled_glyph_t *scaled_glyph,
 	scaled_glyph->has_info &= ~CAIRO_SCALED_GLYPH_INFO_RECORDING_SURFACE;
 }
 
+/**
+ * _cairo_scaled_glyph_set_color_surface:
+ * @scaled_glyph: a #cairo_scaled_glyph_t
+ * @scaled_font: a #cairo_scaled_font_t
+ * @surface: The image surface
+ * @foreground_color: The foreground color that was used to render the
+ * glyph, or NULL if foreground color not required.
+ */
 void
-_cairo_scaled_glyph_set_color_surface (cairo_scaled_glyph_t *scaled_glyph,
-	                               cairo_scaled_font_t *scaled_font,
+_cairo_scaled_glyph_set_color_surface (cairo_scaled_glyph_t  *scaled_glyph,
+	                               cairo_scaled_font_t   *scaled_font,
 	                               cairo_image_surface_t *surface,
-				       cairo_bool_t uses_foreground_color)
+				       const cairo_color_t   *foreground_color)
 {
     if (scaled_glyph->color_surface != NULL)
 	cairo_surface_destroy (&scaled_glyph->color_surface->base);
@@ -2683,7 +2703,9 @@ _cairo_scaled_glyph_set_color_surface (cairo_scaled_glyph_t *scaled_glyph,
     /* sanity check the backend glyph contents */
     _cairo_debug_check_image_surface_is_defined (&surface->base);
     scaled_glyph->color_surface = surface;
-    scaled_glyph->uses_foreground_color = uses_foreground_color;
+    scaled_glyph->image_uses_foreground_color = foreground_color != NULL;
+    if (foreground_color)
+	scaled_glyph->foreground_color = *foreground_color;
 
     if (surface != NULL)
 	scaled_glyph->has_info |= CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE;
@@ -2814,8 +2836,11 @@ _cairo_scaled_font_free_last_glyph (cairo_scaled_font_t *scaled_font,
  * @index: the glyph to create
  * @info: a #cairo_scaled_glyph_info_t marking which portions of
  * the glyph should be filled in.
- * @foreground_color - foreground color to use when rendering color fonts. Use NULL
- * if not requesting CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE or foreground color is unknown.
+ * @foreground_color - foreground color to use when rendering color
+ * fonts. Use NULL if not requesting
+ * CAIRO_SCALED_GLYPH_INFO_RECORDING_SURFACE or
+ * CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE, or foreground color is
+ * unknown.
  * @scaled_glyph_ret: a #cairo_scaled_glyph_t where the glyph
  * is returned.
  *
@@ -2909,14 +2934,23 @@ _cairo_scaled_glyph_lookup (cairo_scaled_font_t *scaled_font,
 	scaled_glyph->color_glyph_set && !scaled_glyph->color_glyph)
 	return CAIRO_INT_STATUS_UNSUPPORTED;
 
-    /* If requesting a color surface for a glyph that has used the
-     * foreground color to render the color_surface, and the
-     * foreground color has changed, request a new image. */
-    if ((info & CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE) &&
-	scaled_glyph->uses_foreground_color &&
+    /* If requesting a color surface or recording for a glyph that has
+     * used the foreground color to render the color_surface, and the
+     * foreground color has changed, request a new image and/or
+     * recording. */
+
+    if (info & CAIRO_SCALED_GLYPH_INFO_RECORDING_SURFACE &&
+	scaled_glyph->recording_uses_foreground_color &&
+	!_cairo_color_equal (foreground_color, &scaled_glyph->foreground_color))
+    {
+	need_info |= CAIRO_SCALED_GLYPH_INFO_RECORDING_SURFACE;
+    }
+
+    if (info & CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE &&
+	scaled_glyph->image_uses_foreground_color &&
 	!_cairo_color_equal (foreground_color, &scaled_glyph->foreground_color))
     {
-	need_info |= CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE;
+	    need_info |= CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE;
     }
 
     if (need_info) {