cs_radial_gradient.glsl (2421B)
1 /* This Source Code Form is subject to the terms of the Mozilla Public 2 * License, v. 2.0. If a copy of the MPL was not distributed with this 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 4 5 #include shared,rect,render_task,gpu_buffer,gradient 6 7 varying highp vec2 v_pos; 8 9 // Start radius. Packed in to a vector to work around bug 1630356. 10 flat varying highp vec2 v_start_radius; 11 12 #ifdef WR_VERTEX_SHADER 13 14 #define EXTEND_MODE_REPEAT 1 15 16 PER_INSTANCE in vec4 aTaskRect; 17 PER_INSTANCE in vec2 aCenter; 18 PER_INSTANCE in vec2 aScale; 19 PER_INSTANCE in float aStartRadius; 20 PER_INSTANCE in float aEndRadius; 21 PER_INSTANCE in float aXYRatio; 22 PER_INSTANCE in int aExtendMode; 23 PER_INSTANCE in int aGradientStopsAddress; 24 25 void main(void) { 26 // Store 1/rd where rd = end_radius - start_radius 27 // If rd = 0, we can't get its reciprocal. Instead, just use a zero scale. 28 float rd = aEndRadius - aStartRadius; 29 float radius_scale = rd != 0.0 ? 1.0 / rd : 0.0; 30 31 vec2 pos = mix(aTaskRect.xy, aTaskRect.zw, aPosition.xy); 32 gl_Position = uTransform * vec4(pos, 0.0, 1.0); 33 34 v_start_radius.x = aStartRadius * radius_scale; 35 36 // Transform all coordinates by the y scale so the 37 // fragment shader can work with circles 38 39 // v_pos is in a coordinate space relative to the task rect 40 // (so it is independent of the task origin). 41 v_pos = ((aTaskRect.zw - aTaskRect.xy) * aPosition.xy * aScale - aCenter) * radius_scale; 42 v_pos.y *= aXYRatio; 43 44 v_gradient_repeat.x = float(aExtendMode == EXTEND_MODE_REPEAT); 45 v_gradient_address.x = aGradientStopsAddress; 46 } 47 #endif 48 49 50 #ifdef WR_FRAGMENT_SHADER 51 52 void main(void) { 53 // Solve for t in length(pd) = v_start_radius + t * rd 54 float offset = length(v_pos) - v_start_radius.x; 55 56 oFragColor = sample_gradient(offset); 57 } 58 59 #ifdef SWGL_DRAW_SPAN 60 void swgl_drawSpanRGBA8() { 61 int address = swgl_validateGradient(sGpuBufferF, get_gpu_buffer_uv(v_gradient_address.x), 62 int(GRADIENT_ENTRIES + 2.0)); 63 if (address < 0) { 64 return; 65 } 66 #ifdef WR_FEATURE_DITHERING 67 swgl_commitDitheredRadialGradientRGBA8(sGpuBufferF, address, GRADIENT_ENTRIES, v_gradient_repeat.x != 0.0, 68 v_pos, v_start_radius.x); 69 #else 70 swgl_commitRadialGradientRGBA8(sGpuBufferF, address, GRADIENT_ENTRIES, v_gradient_repeat.x != 0.0, v_pos, v_start_radius.x); 71 #endif 72 } 73 #endif 74 75 #endif