playcanvas/build/playcanvas/src/scene/shader-lib/chunks/common/frag/reproject.js

PlayCanvas WebGL game engine

import decodePS from './decode.js';
import encodePS from './encode.js';

var reprojectPS = "\nvarying vec2 vUv0;\n#ifdef CUBEMAP_SOURCE\n	uniform samplerCube sourceCube;\n#else\n	uniform sampler2D sourceTex;\n#endif\n#ifdef USE_SAMPLES_TEX\n	uniform sampler2D samplesTex;\n	uniform vec2 samplesTexInverseSize;\n#endif\nuniform vec3 params;\nfloat targetFace() { return params.x; }\nfloat targetTotalPixels() { return params.y; }\nfloat sourceTotalPixels() { return params.z; }\nfloat PI = 3.141592653589793;\nfloat saturate(float x) {\n	return clamp(x, 0.0, 1.0);\n}\n" + decodePS + "\n" + encodePS + "\nvec3 modifySeams(vec3 dir, float scale) {\n	vec3 adir = abs(dir);\n	float M = max(max(adir.x, adir.y), adir.z);\n	return dir / M * vec3(\n		adir.x == M ? 1.0 : scale,\n		adir.y == M ? 1.0 : scale,\n		adir.z == M ? 1.0 : scale\n	);\n}\nvec2 toSpherical(vec3 dir) {\n	return vec2(dir.xz == vec2(0.0) ? 0.0 : atan(dir.x, dir.z), asin(dir.y));\n}\nvec3 fromSpherical(vec2 uv) {\n	return vec3(cos(uv.y) * sin(uv.x),\n				sin(uv.y),\n				cos(uv.y) * cos(uv.x));\n}\nvec3 getDirectionEquirect() {\n	return fromSpherical((vec2(vUv0.x, 1.0 - vUv0.y) * 2.0 - 1.0) * vec2(PI, PI * 0.5));\n}\nfloat signNotZero(float k){\n	return(k >= 0.0) ? 1.0 : -1.0;\n}\nvec2 signNotZero(vec2 v) {\n	return vec2(signNotZero(v.x), signNotZero(v.y));\n}\nvec3 octDecode(vec2 o) {\n	vec3 v = vec3(o.x, 1.0 - abs(o.x) - abs(o.y), o.y);\n	if (v.y < 0.0) {\n		v.xz = (1.0 - abs(v.zx)) * signNotZero(v.xz);\n	}\n	return normalize(v);\n}\nvec3 getDirectionOctahedral() {\n	return octDecode(vec2(vUv0.x, 1.0 - vUv0.y) * 2.0 - 1.0);\n}\nvec2 octEncode(in vec3 v) {\n	float l1norm = abs(v.x) + abs(v.y) + abs(v.z);\n	vec2 result = v.xz * (1.0 / l1norm);\n	if (v.y < 0.0) {\n		result = (1.0 - abs(result.yx)) * signNotZero(result.xy);\n	}\n	return result;\n}\n#ifdef CUBEMAP_SOURCE\n	vec4 sampleCubemap(vec3 dir) {\n		return textureCube(sourceCube, modifySeams(dir, 1.0));\n	}\n	vec4 sampleCubemap(vec2 sph) {\n	return sampleCubemap(fromSpherical(sph));\n}\n	vec4 sampleCubemap(vec3 dir, float mipLevel) {\n		return textureCubeLod(sourceCube, modifySeams(dir, 1.0), mipLevel);\n	}\n	vec4 sampleCubemap(vec2 sph, float mipLevel) {\n		return sampleCubemap(fromSpherical(sph), mipLevel);\n	}\n#else\n	vec4 sampleEquirect(vec2 sph) {\n		vec2 uv = sph / vec2(PI * 2.0, PI) + 0.5;\n		return texture2D(sourceTex, vec2(uv.x, 1.0 - uv.y));\n	}\n	vec4 sampleEquirect(vec3 dir) {\n		return sampleEquirect(toSpherical(dir));\n	}\n	vec4 sampleEquirect(vec2 sph, float mipLevel) {\n		vec2 uv = sph / vec2(PI * 2.0, PI) + 0.5;\n		return texture2DLod(sourceTex, vec2(uv.x, 1.0 - uv.y), mipLevel);\n	}\n	vec4 sampleEquirect(vec3 dir, float mipLevel) {\n		return sampleEquirect(toSpherical(dir), mipLevel);\n	}\n	vec4 sampleOctahedral(vec3 dir) {\n		vec2 uv = octEncode(dir) * 0.5 + 0.5;\n		return texture2D(sourceTex, vec2(uv.x, 1.0 - uv.y));\n	}\n	vec4 sampleOctahedral(vec2 sph) {\n		return sampleOctahedral(fromSpherical(sph));\n	}\n	vec4 sampleOctahedral(vec3 dir, float mipLevel) {\n		vec2 uv = octEncode(dir) * 0.5 + 0.5;\n		return texture2DLod(sourceTex, vec2(uv.x, 1.0 - uv.y), mipLevel);\n	}\n	vec4 sampleOctahedral(vec2 sph, float mipLevel) {\n		return sampleOctahedral(fromSpherical(sph), mipLevel);\n	}\n#endif\nvec3 getDirectionCubemap() {\n	vec2 st = vUv0 * 2.0 - 1.0;\n	float face = targetFace();\n	vec3 vec;\n	if (face == 0.0) {\n		vec = vec3(1, -st.y, -st.x);\n	} else if (face == 1.0) {\n		vec = vec3(-1, -st.y, st.x);\n	} else if (face == 2.0) {\n		vec = vec3(st.x, 1, st.y);\n	} else if (face == 3.0) {\n		vec = vec3(st.x, -1, -st.y);\n	} else if (face == 4.0) {\n		vec = vec3(st.x, -st.y, 1);\n	} else {\n		vec = vec3(-st.x, -st.y, -1);\n	}\n	return normalize(modifySeams(vec, 1.0));\n}\nmat3 matrixFromVector(vec3 n) {\n	float a = 1.0 / (1.0 + n.z);\n	float b = -n.x * n.y * a;\n	vec3 b1 = vec3(1.0 - n.x * n.x * a, b, -n.x);\n	vec3 b2 = vec3(b, 1.0 - n.y * n.y * a, -n.y);\n	return mat3(b1, b2, n);\n}\nmat3 matrixFromVectorSlow(vec3 n) {\n	vec3 up = (1.0 - abs(n.y) <= 0.0000001) ? vec3(0.0, 0.0, n.y > 0.0 ? 1.0 : -1.0) : vec3(0.0, 1.0, 0.0);\n	vec3 x = normalize(cross(up, n));\n	vec3 y = cross(n, x);\n	return mat3(x, y, n);\n}\nvec4 reproject() {\n	if (NUM_SAMPLES <= 1) {\n		return ENCODE_FUNC(DECODE_FUNC(SOURCE_FUNC(TARGET_FUNC())));\n	} else {\n		vec3 t = TARGET_FUNC();\n		vec3 tu = dFdx(t);\n		vec3 tv = dFdy(t);\n		vec3 result = vec3(0.0);\n		for (float u = 0.0; u < NUM_SAMPLES_SQRT; ++u) {\n			for (float v = 0.0; v < NUM_SAMPLES_SQRT; ++v) {\n				result += DECODE_FUNC(SOURCE_FUNC(normalize(t +\n															tu * (u / NUM_SAMPLES_SQRT - 0.5) +\n															tv * (v / NUM_SAMPLES_SQRT - 0.5))));\n			}\n		}\n		return ENCODE_FUNC(result / (NUM_SAMPLES_SQRT * NUM_SAMPLES_SQRT));\n	}\n}\nvec4 unpackFloat = vec4(1.0, 1.0 / 255.0, 1.0 / 65025.0, 1.0 / 16581375.0);\n#ifdef USE_SAMPLES_TEX\n	void unpackSample(int i, out vec3 L, out float mipLevel) {\n		float u = (float(i * 4) + 0.5) * samplesTexInverseSize.x;\n		float v = (floor(u) + 0.5) * samplesTexInverseSize.y;\n		vec4 raw;\n		raw.x = dot(texture2D(samplesTex, vec2(u, v)), unpackFloat); u += samplesTexInverseSize.x;\n		raw.y = dot(texture2D(samplesTex, vec2(u, v)), unpackFloat); u += samplesTexInverseSize.x;\n		raw.z = dot(texture2D(samplesTex, vec2(u, v)), unpackFloat); u += samplesTexInverseSize.x;\n		raw.w = dot(texture2D(samplesTex, vec2(u, v)), unpackFloat);\n		L.xyz = raw.xyz * 2.0 - 1.0;\n		mipLevel = raw.w * 8.0;\n	}\n	vec4 prefilterSamples() {\n		mat3 vecSpace = matrixFromVectorSlow(TARGET_FUNC());\n		vec3 L;\n		float mipLevel;\n		vec3 result = vec3(0.0);\n		float totalWeight = 0.0;\n		for (int i = 0; i < NUM_SAMPLES; ++i) {\n			unpackSample(i, L, mipLevel);\n			result += DECODE_FUNC(SOURCE_FUNC(vecSpace * L, mipLevel)) * L.z;\n			totalWeight += L.z;\n		}\n		return ENCODE_FUNC(result / totalWeight);\n	}\n	vec4 prefilterSamplesUnweighted() {\n		mat3 vecSpace = matrixFromVectorSlow(TARGET_FUNC());\n		vec3 L;\n		float mipLevel;\n		vec3 result = vec3(0.0);\n		float totalWeight = 0.0;\n		for (int i = 0; i < NUM_SAMPLES; ++i) {\n			unpackSample(i, L, mipLevel);\n			result += DECODE_FUNC(SOURCE_FUNC(vecSpace * L, mipLevel));\n		}\n		return ENCODE_FUNC(result / float(NUM_SAMPLES));\n	}\n#endif\nvoid main(void) {\n	gl_FragColor = PROCESS_FUNC();\n}\n";

export { reprojectPS as default };