osci-render/Source/visualiser/AfterglowFragmentShader.glsl

24 wiersze
678 B
GLSL

std::string afterglowFragmentShader = R"(
uniform sampler2D uTexture0;
varying vec2 vTexCoord;
uniform float fadeAmount;
uniform float afterglowAmount;
// tanh is not available in GLSL ES 1.0, so we define it here.
float hypTan(float x) {
return (exp(x) - exp(-x)) / (exp(x) + exp(-x));
}
void main() {
vec4 line = texture2D(uTexture0, vTexCoord);
float x = min(line.r / afterglowAmount, 10.0);
float minFade = 0.1 * (1.0 - clamp(afterglowAmount / 10.0, 0.0, 1.0));
float fade = fadeAmount * ((1.0 - minFade) * hypTan(x) + minFade);
fade = clamp(fade, 0.0, fadeAmount);
gl_FragColor = vec4(0.0, 0.0, 0.0, fade);
}
)";