cs_conic_gradient.glsl (2238B)
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 #define PI 3.141592653589793 8 9 varying highp vec2 v_pos; 10 11 flat varying highp vec2 v_center; 12 13 // x: start offset, y: offset scale, z: angle 14 // Packed in to a vector to work around bug 1630356. 15 flat varying highp vec3 v_start_offset_offset_scale_angle_vec; 16 #define v_start_offset v_start_offset_offset_scale_angle_vec.x 17 #define v_offset_scale v_start_offset_offset_scale_angle_vec.y 18 #define v_angle v_start_offset_offset_scale_angle_vec.z 19 20 #ifdef WR_VERTEX_SHADER 21 22 #define EXTEND_MODE_REPEAT 1 23 24 PER_INSTANCE in vec4 aTaskRect; 25 PER_INSTANCE in vec2 aCenter; 26 PER_INSTANCE in vec2 aScale; 27 PER_INSTANCE in float aStartOffset; 28 PER_INSTANCE in float aEndOffset; 29 PER_INSTANCE in float aAngle; 30 PER_INSTANCE in int aExtendMode; 31 PER_INSTANCE in int aGradientStopsAddress; 32 33 void main(void) { 34 // Store 1/d where d = end_offset - start_offset 35 // If d = 0, we can't get its reciprocal. Instead, just use a zero scale. 36 float d = aEndOffset - aStartOffset; 37 v_offset_scale = d != 0.0 ? 1.0 / d : 0.0; 38 39 vec2 pos = mix(aTaskRect.xy, aTaskRect.zw, aPosition.xy); 40 gl_Position = uTransform * vec4(pos, 0.0, 1.0); 41 42 v_angle = PI / 2.0 - aAngle; 43 v_start_offset = aStartOffset * v_offset_scale; 44 45 // v_pos and v_center are in a coordinate space relative to the task rect 46 // (so they are independent of the task origin). 47 v_center = aCenter * v_offset_scale; 48 v_pos = (aTaskRect.zw - aTaskRect.xy) * aPosition.xy * v_offset_scale * aScale; 49 50 v_gradient_repeat.x = float(aExtendMode == EXTEND_MODE_REPEAT); 51 v_gradient_address.x = aGradientStopsAddress; 52 } 53 #endif 54 55 56 #ifdef WR_FRAGMENT_SHADER 57 58 void main(void) { 59 // Use inverse trig to find the angle offset from the relative position. 60 vec2 current_dir = v_pos - v_center; 61 float current_angle = atan(current_dir.y, current_dir.x) + v_angle; 62 float offset = fract(current_angle / (2.0 * PI)) * v_offset_scale - v_start_offset; 63 64 oFragColor = sample_gradient(offset); 65 } 66 67 #endif