#version 300 es precision mediump float; const int NUM_TEXTURES = 16; uniform sampler2D uTextures[NUM_TEXTURES]; uniform float textureIndex; in vec2 v_textureCoord; out vec4 outColor; vec4 getTextureColor(float textureSlot, vec2 vTexturePoint); void main() { vec4 color = getTextureColor(textureIndex, v_textureCoord); outColor = vec4(color.xyzw); } const float threshold = 0.00001; vec4 getTextureColor(float textureSlot, vec2 vTexturePoint) { if (abs(0.0 - textureSlot) < threshold) { return texture(uTextures[0], vTexturePoint); } if (abs(1.0 - textureSlot) < threshold) { return texture(uTextures[1], vTexturePoint); } if (abs(2.0 - textureSlot) < threshold) { return texture(uTextures[2], vTexturePoint); } if (abs(3.0 - textureSlot) < threshold) { return texture(uTextures[3], vTexturePoint); } if (abs(4.0 - textureSlot) < threshold) { return texture(uTextures[4], vTexturePoint); } if (abs(5.0 - textureSlot) < threshold) { return texture(uTextures[5], vTexturePoint); } if (abs(6.0 - textureSlot) < threshold) { return texture(uTextures[6], vTexturePoint); } if (abs(7.0 - textureSlot) < threshold) { return texture(uTextures[7], vTexturePoint); } if (abs(8.0 - textureSlot) < threshold) { return texture(uTextures[8], vTexturePoint); } if (abs(9.0 - textureSlot) < threshold) { return texture(uTextures[9], vTexturePoint); } if (abs(10.0 - textureSlot) < threshold) { return texture(uTextures[10], vTexturePoint); } if (abs(11.0 - textureSlot) < threshold) { return texture(uTextures[11], vTexturePoint); } if (abs(12.0 - textureSlot) < threshold) { return texture(uTextures[12], vTexturePoint); } if (abs(13.0 - textureSlot) < threshold) { return texture(uTextures[13], vTexturePoint); } if (abs(14.0 - textureSlot) < threshold) { return texture(uTextures[14], vTexturePoint); } if (abs(15.0 - textureSlot) < threshold) { return texture(uTextures[15], vTexturePoint); } return texture(uTextures[0], vTexturePoint); }

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