// deck.gl
// SPDX-License-Identifier: MIT
// Copyright (c) vis.gl contributors

// Inspired by screen-grid-layer vertex shader in deck.gl

export default `\
#version 300 es
#define SHADER_NAME heatp-map-layer-vertex-shader

uniform sampler2D maxTexture;

in vec3 positions;
in vec2 texCoords;

out vec2 vTexCoords;
out float vIntensityMin;
out float vIntensityMax;

void main(void) {
  gl_Position = project_position_to_clipspace(positions, vec3(0.0), vec3(0.0));
  vTexCoords = texCoords;
  vec4 maxTexture = texture(maxTexture, vec2(0.5));
  float maxValue = triangle.aggregationMode < 0.5 ? maxTexture.r : maxTexture.g;
  float minValue = maxValue * triangle.threshold;
  if (triangle.colorDomain[1] > 0.) {
    // if user specified custom domain use it.
    maxValue = triangle.colorDomain[1];
    minValue = triangle.colorDomain[0];
  }
  vIntensityMax = triangle.intensity / maxValue;
  vIntensityMin = triangle.intensity / minValue;
}
`;