BLT-With-Graphics-Template/include/blt/gfx/renderer/2d_textured_circle.frag

#ifdef __cplusplus
#include <string>
const std::string shader_2d_textured_cirlce_frag = R"("
#version 300 es
precision mediump float;

out vec4 FragColor;
in vec2 uv;
in vec2 pos;

uniform sampler2D tex;
uniform vec4 color;
uniform vec4 use_texture;

const float offset = 1.0 / 32.0;

vec4 linear_iter(vec4 i, vec4 p, float factor){
    return (i + p) * factor;
}

void main() {
    float xs = pos.x * pos.x;
    float ys = pos.y * pos.y;
    float ts = xs + ys;
    const float sq = 0.5 * 0.5;
    if (ts > sq)
        discard;
    if (ts + offset > sq)
        FragColor = vec4(1.0, 1.0, 1.0, 1.0);
    else
        FragColor = (texture(tex, uv) * use_texture) + color;
}

")";
#endif