impeller/entity/shaders/texture_uv_fill.vert

// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <impeller/conversions.glsl>
#include <impeller/types.glsl>

// A shader that computes texture UVs from a normalizing transform.
uniform FrameInfo {
  mat4 mvp;
  // A normlizing transform created from the texture bounds and effect transform
  mat4 uv_transform;
  float texture_sampler_y_coord_scale;
}
frame_info;

in vec2 position;

out vec2 v_texture_coords;

void main() {
  gl_Position = frame_info.mvp * vec4(position, 0.0, 1.0);
  vec2 texture_coords = (frame_info.uv_transform * vec4(position, 0.0, 1.0)).xy;
  v_texture_coords =
      IPRemapCoords(texture_coords, frame_info.texture_sampler_y_coord_scale);
}