1 files changed, 95 insertions, 0 deletions
diff --git a/gfx/wr/webrender/res/brush_conic_gradient.glsl b/gfx/wr/webrender/res/brush_conic_gradient.glsl
new file mode 100644
index 0000000000..cdc5a8a241
--- /dev/null
+++ b/gfx/wr/webrender/res/brush_conic_gradient.glsl
@@ -0,0 +1,95 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#define VECS_PER_SPECIFIC_BRUSH 2
+
+#include shared,prim_shared,brush,gradient_shared
+
+flat varying vec2 v_center;
+flat varying float v_start_offset;
+flat varying float v_offset_scale;
+flat varying float v_angle;
+
+#define PI                  3.141592653589793
+
+#ifdef WR_VERTEX_SHADER
+
+struct ConicGradient {
+    vec2 center_point;
+    vec2 start_end_offset;
+    float angle;
+    int extend_mode;
+    vec2 stretch_size;
+};
+
+ConicGradient fetch_gradient(int address) {
+    vec4 data[2] = fetch_from_gpu_cache_2(address);
+    return ConicGradient(
+        data[0].xy,
+        data[0].zw,
+        float(data[1].x),
+        int(data[1].y),
+        data[1].zw
+    );
+}
+
+void brush_vs(
+    VertexInfo vi,
+    int prim_address,
+    RectWithSize local_rect,
+    RectWithSize segment_rect,
+    ivec4 prim_user_data,
+    int specific_resource_address,
+    mat4 transform,
+    PictureTask pic_task,
+    int brush_flags,
+    vec4 texel_rect
+) {
+    ConicGradient gradient = fetch_gradient(prim_address);
+
+    write_gradient_vertex(
+        vi,
+        local_rect,
+        segment_rect,
+        prim_user_data,
+        brush_flags,
+        texel_rect,
+        gradient.extend_mode,
+        gradient.stretch_size
+    );
+
+    v_center = gradient.center_point;
+    v_angle = PI / 2.0 - gradient.angle;
+    v_start_offset = gradient.start_end_offset.x;
+    if (gradient.start_end_offset.x != gradient.start_end_offset.y) {
+      // Store 1/scale where scale = end_offset - start_offset
+      v_offset_scale = 1.0 / (gradient.start_end_offset.y - gradient.start_end_offset.x);
+    } else {
+      // If scale = 0, we can't get its reciprocal. Instead, just use a zero scale.
+      v_offset_scale = 0.0;
+    }
+}
+#endif
+
+#ifdef WR_FRAGMENT_SHADER
+Fragment brush_fs() {
+    vec2 pos = compute_gradient_pos();
+
+    // Rescale UV to actual repetition size. This can't be done in the vertex
+    // shader due to the use of atan() below.
+    pos *= v_repeated_size;
+
+    vec2 current_dir = pos - v_center;
+    float current_angle = atan(current_dir.y, current_dir.x) + v_angle;
+    float offset = (fract(current_angle / (2.0 * PI)) - v_start_offset) * v_offset_scale;
+
+    vec4 color = sample_gradient(offset);
+
+#ifdef WR_FEATURE_ALPHA_PASS
+    color *= init_transform_fs(v_local_pos);
+#endif
+
+    return Fragment(color);
+}
+#endif