add more per-platform font options to FontInstancePlatformOptions

webrender/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "webrender"
-version = "0.52.0"
+version = "0.52.1"
 authors = ["Glenn Watson <gw@intuitionlibrary.com>"]
 license = "MPL-2.0"
 repository = "https://github.com/servo/webrender"

webrender/res/cs_text_run.glsl

@@ -38,7 +38,7 @@ void main(void) {
     // Glyphs size is already in device-pixels.
     // The render task origin is in device-pixels. Offset that by
     // the glyph offset, relative to its primitive bounding rect.
-    vec2 size = res.uv_rect.zw - res.uv_rect.xy;
+    vec2 size = (res.uv_rect.zw - res.uv_rect.xy) * res.scale;
     vec2 local_pos = glyph.offset + vec2(res.offset.x, -res.offset.y) / uDevicePixelRatio;
     vec2 origin = prim.task.render_target_origin +
                   uDevicePixelRatio * (local_pos + shadow.offset - shadow_geom.local_rect.p0);

webrender/res/prim_shared.glsl

@@ -627,11 +627,12 @@ struct GlyphResource {
     vec4 uv_rect;
     float layer;
     vec2 offset;
+    float scale;
 };
 
 GlyphResource fetch_glyph_resource(int address) {
     vec4 data[2] = fetch_from_resource_cache_2(address);
-    return GlyphResource(data[0], data[1].x, data[1].yz);
+    return GlyphResource(data[0], data[1].x, data[1].yz, data[1].w);
 }
 
 struct ImageResource {

webrender/res/ps_text_run.glsl

@@ -30,7 +30,7 @@ void main(void) {
                      vec2(res.offset.x, -res.offset.y) / uDevicePixelRatio;
 
     RectWithSize local_rect = RectWithSize(local_pos,
-                                           (res.uv_rect.zw - res.uv_rect.xy) / uDevicePixelRatio);
+                                           (res.uv_rect.zw - res.uv_rect.xy) * res.scale / uDevicePixelRatio);
 
 #ifdef WR_FEATURE_TRANSFORM
     TransformVertexInfo vi = write_transform_vertex(local_rect,
@@ -57,7 +57,7 @@ void main(void) {
     vec2 st0 = res.uv_rect.xy / texture_size;
     vec2 st1 = res.uv_rect.zw / texture_size;
 
-    vColor = text.color;
+    vColor = vec4(text.color.rgb * text.color.a, text.color.a);
     vUv = vec3(mix(st0, st1, f), res.layer);
     vUvBorder = (res.uv_rect + vec4(0.5, 0.5, -0.5, -0.5)) / texture_size.xyxy;
 }
@@ -71,13 +71,14 @@ void main(void) {
     oFragColor = texture(sColor0, tc);
 #else
     vec4 color = texture(sColor0, tc) * vColor;
+    float alpha = 1.0;
 #ifdef WR_FEATURE_TRANSFORM
     float a = 0.0;
     init_transform_fs(vLocalPos, a);
-    color.a *= a;
+    alpha *= a;
 #endif
-    color.a = min(color.a, do_clip());
-    oFragColor = color;
+    alpha = min(alpha, do_clip());
+    oFragColor = color * alpha;
 #endif
 }
 #endif

webrender/src/frame_builder.rs

@@ -10,7 +10,7 @@ use api::{GlyphInstance, GlyphOptions, GradientStop, HitTestFlags, HitTestItem,
 use api::{ImageKey, ImageRendering, ItemRange, ItemTag, LayerPoint, LayerPrimitiveInfo, LayerRect};
 use api::{LayerSize, LayerToScrollTransform, LayerVector2D, LayoutVector2D, LineOrientation};
 use api::{LineStyle, LocalClip, POINT_RELATIVE_TO_PIPELINE_VIEWPORT, PipelineId, RepeatMode};
-use api::{ScrollSensitivity, SubpixelDirection, Shadow, TileOffset, TransformStyle};
+use api::{ScrollSensitivity, Shadow, TileOffset, TransformStyle};
 use api::{WorldPixel, WorldPoint, YuvColorSpace, YuvData, device_length};
 use app_units::Au;
 use border::ImageBorderSegment;
@@ -1132,19 +1132,18 @@ impl FrameBuilder {
         // TODO(gw): Use a proper algorithm to select
         // whether this item should be rendered with
         // subpixel AA!
-        let mut default_render_mode = self.config
+        let mut render_mode = self.config
             .default_font_render_mode
             .limit_by(font.render_mode);
         if let Some(options) = glyph_options {
-            default_render_mode = default_render_mode.limit_by(options.render_mode);
+            render_mode = render_mode.limit_by(options.render_mode);
         }
 
         // There are some conditions under which we can't use
         // subpixel text rendering, even if enabled.
-        let mut normal_render_mode = default_render_mode;
-        if normal_render_mode == FontRenderMode::Subpixel {
+        if render_mode == FontRenderMode::Subpixel {
             if color.a != 1.0 {
-                normal_render_mode = FontRenderMode::Alpha;
+                render_mode = FontRenderMode::Alpha;
             }
 
             // text on a stacking context that has filters
@@ -1155,36 +1154,17 @@ impl FrameBuilder {
             if let Some(sc_index) = self.stacking_context_stack.last() {
                 let stacking_context = &self.stacking_context_store[sc_index.0];
                 if stacking_context.composite_ops.count() > 0 {
-                    normal_render_mode = FontRenderMode::Alpha;
+                    render_mode = FontRenderMode::Alpha;
                 }
             }
         }
 
-        let color = match font.render_mode {
-            FontRenderMode::Bitmap => ColorF::new(1.0, 1.0, 1.0, 1.0),
-            FontRenderMode::Subpixel |
-            FontRenderMode::Alpha |
-            FontRenderMode::Mono => *color,
-        };
-
-        // Shadows never use subpixel AA, but need to respect the alpha/mono flag
-        // for reftests.
-        let (shadow_render_mode, subpx_dir) = match default_render_mode {
-            FontRenderMode::Subpixel | FontRenderMode::Alpha => {
-                // TODO(gw): Expose subpixel direction in API once WR supports
-                //           vertical text runs.
-                (FontRenderMode::Alpha, font.subpx_dir)
-            }
-            FontRenderMode::Mono => (FontRenderMode::Mono, SubpixelDirection::None),
-            FontRenderMode::Bitmap => (FontRenderMode::Bitmap, font.subpx_dir),
-        };
-
         let prim_font = FontInstance::new(
             font.font_key,
             font.size,
-            color,
-            normal_render_mode,
-            subpx_dir,
+            *color,
+            render_mode,
+            font.subpx_dir,
             font.platform_options,
             font.variations.clone(),
             font.synthetic_italics,
@@ -1195,9 +1175,7 @@ impl FrameBuilder {
             glyph_count,
             glyph_gpu_blocks: Vec::new(),
             glyph_keys: Vec::new(),
-            shadow_render_mode,
             offset: run_offset,
-            color: color,
         };
 
         // Text shadows that have a blur radius of 0 need to be rendered as normal
@@ -1215,16 +1193,13 @@ impl FrameBuilder {
             let shadow = picture_prim.as_shadow();
             if shadow.blur_radius == 0.0 {
                 let mut text_prim = prim.clone();
-                if font.render_mode != FontRenderMode::Bitmap {
-                    text_prim.font.color = shadow.color.into();
-                }
+                text_prim.font.color = shadow.color.into();
                 // If we have translucent text, we need to ensure it won't go
                 // through the subpixel blend mode, which doesn't work with
                 // traditional alpha blending.
                 if shadow.color.a != 1.0 {
                     text_prim.font.render_mode = text_prim.font.render_mode.limit_by(FontRenderMode::Alpha);
                 }
-                text_prim.color = shadow.color;
                 text_prim.offset += shadow.offset;
                 fast_shadow_prims.push(text_prim);
             }

webrender/src/glyph_cache.rs

@@ -13,6 +13,7 @@ pub struct CachedGlyphInfo {
     pub glyph_bytes: Arc<Vec<u8>>,
     pub size: DeviceUintSize,
     pub offset: DevicePoint,
+    pub scale: f32,
 }
 
 pub type GlyphKeyCache = ResourceClassCache<GlyphKey, Option<CachedGlyphInfo>>;

webrender/src/glyph_rasterizer.rs

@@ -3,10 +3,10 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #[cfg(test)]
-use api::{ColorF, FontRenderMode, IdNamespace, LayoutPoint, SubpixelDirection};
+use api::{ColorF, IdNamespace, LayoutPoint};
 use api::{DevicePoint, DeviceUintSize, FontInstance};
-use api::{FontKey, FontTemplate};
-use api::{GlyphDimensions, GlyphKey};
+use api::{FontKey, FontTemplate, FontRenderMode, ColorU};
+use api::{GlyphDimensions, GlyphKey, SubpixelDirection};
 use api::{ImageData, ImageDescriptor, ImageFormat};
 #[cfg(test)]
 use app_units::Au;
@@ -144,6 +144,29 @@ impl GlyphRasterizer {
         self.fonts_to_remove.push(font_key);
     }
 
+    pub fn prepare_font(&self, font: &mut FontInstance) {
+        // In alpha/mono mode, the color of the font is irrelevant.
+        // Forcing it to black in those cases saves rasterizing glyphs
+        // of different colors when not needed.
+        match font.render_mode {
+            FontRenderMode::Mono | FontRenderMode::Bitmap => {
+                font.color = ColorU::new(255, 255, 255, 255);
+                // Subpixel positioning is disabled in mono and bitmap modes.
+                font.subpx_dir = SubpixelDirection::None;
+            }
+            FontRenderMode::Alpha => {
+                font.color = ColorU::new(255, 255, 255, 255);
+            }
+            FontRenderMode::Subpixel => {
+                // In subpixel mode, we only actually need the color if preblending
+                // is used in the font backend.
+                if !FontContext::has_gamma_correct_subpixel_aa() {
+                    font.color = ColorU::new(255, 255, 255, 255);
+                }
+            }
+        }
+    }
+
     pub fn request_glyphs(
         &mut self,
         glyph_cache: &mut GlyphCache,
@@ -183,7 +206,7 @@ impl GlyphRasterizer {
                                 },
                                 TextureFilter::Linear,
                                 ImageData::Raw(glyph_info.glyph_bytes.clone()),
-                                [glyph_info.offset.x, glyph_info.offset.y],
+                                [glyph_info.offset.x, glyph_info.offset.y, glyph_info.scale],
                                 None,
                                 gpu_cache,
                             );
@@ -246,10 +269,10 @@ impl GlyphRasterizer {
             .get_glyph_dimensions(font, glyph_key)
     }
 
-    pub fn is_bitmap_font(&self, font_key: FontKey) -> bool {
+    pub fn is_bitmap_font(&self, font: &FontInstance) -> bool {
         self.font_contexts
             .lock_shared_context()
-            .is_bitmap_font(font_key)
+            .is_bitmap_font(font)
     }
 
     pub fn get_glyph_index(&mut self, font_key: FontKey, ch: char) -> Option<u32> {
@@ -312,7 +335,7 @@ impl GlyphRasterizer {
                         },
                         TextureFilter::Linear,
                         ImageData::Raw(glyph_bytes.clone()),
-                        [glyph.left, glyph.top],
+                        [glyph.left, glyph.top, glyph.scale],
                         None,
                         gpu_cache,
                     );
@@ -321,6 +344,7 @@ impl GlyphRasterizer {
                         glyph_bytes,
                         size: DeviceUintSize::new(glyph.width, glyph.height),
                         offset: DevicePoint::new(glyph.left, glyph.top),
+                        scale: glyph.scale,
                     })
                 } else {
                     None

webrender/src/platform/macos/font.rs

@@ -42,6 +42,7 @@ pub struct RasterizedGlyph {
     pub left: f32,
     pub width: u32,
     pub height: u32,
+    pub scale: f32,
     pub bytes: Vec<u8>,
 }
 
@@ -52,6 +53,7 @@ impl RasterizedGlyph {
             left: 0.0,
             width: 0,
             height: 0,
+            scale: 1.0,
             bytes: vec![],
         }
     }
@@ -422,18 +424,20 @@ impl FontContext {
         }
     }
 
-    pub fn is_bitmap_font(&mut self, font_key: FontKey) -> bool {
-        match self.get_ct_font(font_key, Au(16 * 60), &[]) {
+    pub fn is_bitmap_font(&mut self, font: &FontInstance) -> bool {
+        match self.get_ct_font(font.font_key, font.size, &font.variations) {
             Some(ref ct_font) => {
                 let traits = ct_font.symbolic_traits();
                 (traits & kCTFontColorGlyphsTrait) != 0
             }
-            None => {
-                false
-            }
+            None => false,
         }
     }
 
+    pub fn has_gamma_correct_subpixel_aa() -> bool {
+        true
+    }
+
     pub fn rasterize_glyph(
         &mut self,
         font: &FontInstance,
@@ -585,6 +589,7 @@ impl FontContext {
             top: metrics.rasterized_ascent as f32,
             width: metrics.rasterized_width,
             height: metrics.rasterized_height,
+            scale: 1.0,
             bytes: rasterized_pixels,
         })
     }