Files
filament/shaders/src/depth_main.fs
2023-11-16 12:57:54 -08:00

96 lines
3.1 KiB
GLSL

#if defined(VARIANT_HAS_VSM)
layout(location = 0) out highp vec4 fragColor;
#elif defined(VARIANT_HAS_PICKING)
# if __VERSION__ == 100
highp vec4 outPicking;
# else
# if MATERIAL_FEATURE_LEVEL == 0
layout(location = 0) out highp vec4 outPicking;
# else
layout(location = 0) out highp vec2 outPicking;
# endif
# endif
#else
// not color output
#endif
//------------------------------------------------------------------------------
// Depth
//
// note: VARIANT_HAS_VSM and VARIANT_HAS_PICKING are mutually exclusive
//------------------------------------------------------------------------------
highp vec2 computeDepthMomentsVSM(const highp float depth);
void main() {
filament_lodBias = frameUniforms.lodBias;
initObjectUniforms();
#if defined(MATERIAL_HAS_CUSTOM_DEPTH) || defined(BLEND_MODE_MASKED) || ((defined(BLEND_MODE_TRANSPARENT) || defined(BLEND_MODE_FADE)) && defined(MATERIAL_HAS_TRANSPARENT_SHADOW))
MaterialInputs inputs;
initMaterial(inputs);
material(inputs);
float alpha = inputs.baseColor.a;
#if defined(BLEND_MODE_MASKED)
if (alpha < getMaskThreshold()) {
discard;
}
#endif
#if defined(MATERIAL_HAS_TRANSPARENT_SHADOW)
// Interleaved gradient noise, see dithering.fs
float noise = interleavedGradientNoise(gl_FragCoord.xy);
if (noise >= alpha) {
discard;
}
#endif
#endif
#if defined(VARIANT_HAS_VSM)
// interpolated depth is stored in vertex_worldPosition.w (see main.vs)
// we always compute the "negative" side of ELVSM because the cost is small, and this allows
// EVSM/ELVSM choice to be done on the CPU side more easily.
highp float depth = vertex_worldPosition.w;
depth = exp(frameUniforms.vsmExponent * depth);
fragColor.xy = computeDepthMomentsVSM(depth);
fragColor.zw = computeDepthMomentsVSM(-1.0 / depth); // requires at least RGBA16F
#elif defined(VARIANT_HAS_PICKING)
#if FILAMENT_EFFECTIVE_VERSION == 100
outPicking.a = mod(float(object_uniforms_objectId / 65536), 256.0) / 255.0;
outPicking.b = mod(float(object_uniforms_objectId / 256), 256.0) / 255.0;
outPicking.g = mod(float(object_uniforms_objectId) , 256.0) / 255.0;
outPicking.r = vertex_position.z / vertex_position.w;
#else
outPicking.x = intBitsToFloat(object_uniforms_objectId);
outPicking.y = vertex_position.z / vertex_position.w;
#endif
#if __VERSION__ == 100
gl_FragData[0] = outPicking;
#endif
#else
// that's it
#endif
}
highp vec2 computeDepthMomentsVSM(const highp float depth) {
// computes the moments
// See GPU Gems 3
// https://developer.nvidia.com/gpugems/gpugems3/part-ii-light-and-shadows/chapter-8-summed-area-variance-shadow-maps
highp vec2 moments;
// the first moment is just the depth (average)
moments.x = depth;
// compute the 2nd moment over the pixel extents.
moments.y = depth * depth;
// the local linear approximation is not correct with a warped depth
//highp float dx = dFdx(depth);
//highp float dy = dFdy(depth);
//moments.y += 0.25 * (dx * dx + dy * dy);
return moments;
}