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/* 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/. */
#include shared,rect,render_task,gpu_cache,gpu_buffer,gradient
#define PI 3.141592653589793
varying highp vec2 v_pos;
flat varying highp vec2 v_center;
// x: start offset, y: offset scale, z: angle
// Packed in to a vector to work around bug 1630356.
flat varying highp vec3 v_start_offset_offset_scale_angle_vec;
#define v_start_offset v_start_offset_offset_scale_angle_vec.x
#define v_offset_scale v_start_offset_offset_scale_angle_vec.y
#define v_angle v_start_offset_offset_scale_angle_vec.z
#ifdef WR_VERTEX_SHADER
#define EXTEND_MODE_REPEAT 1
PER_INSTANCE in vec4 aTaskRect;
PER_INSTANCE in vec2 aCenter;
PER_INSTANCE in vec2 aScale;
PER_INSTANCE in float aStartOffset;
PER_INSTANCE in float aEndOffset;
PER_INSTANCE in float aAngle;
PER_INSTANCE in int aExtendMode;
PER_INSTANCE in int aGradientStopsAddress;
void main(void) {
// Store 1/d where d = end_offset - start_offset
// If d = 0, we can't get its reciprocal. Instead, just use a zero scale.
float d = aEndOffset - aStartOffset;
v_offset_scale = d != 0.0 ? 1.0 / d : 0.0;
vec2 pos = mix(aTaskRect.xy, aTaskRect.zw, aPosition.xy);
gl_Position = uTransform * vec4(pos, 0.0, 1.0);
v_angle = PI / 2.0 - aAngle;
v_start_offset = aStartOffset * v_offset_scale;
// v_pos and v_center are in a coordinate space relative to the task rect
// (so they are independent of the task origin).
v_center = aCenter * v_offset_scale;
v_pos = (aTaskRect.zw - aTaskRect.xy) * aPosition.xy * v_offset_scale * aScale;
v_gradient_repeat.x = float(aExtendMode == EXTEND_MODE_REPEAT);
v_gradient_address.x = aGradientStopsAddress;
}
#endif
#ifdef WR_FRAGMENT_SHADER
void main(void) {
// Use inverse trig to find the angle offset from the relative position.
vec2 current_dir = v_pos - v_center;
float current_angle = atan(current_dir.y, current_dir.x) + v_angle;
float offset = fract(current_angle / (2.0 * PI)) * v_offset_scale - v_start_offset;
oFragColor = sample_gradient(offset);
}
#endif
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