You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

1203 lines
40 KiB
JavaScript

import defaultValue from "../Core/defaultValue.js";
import defined from "../Core/defined.js";
import WebGLConstants from "../Core/WebGLConstants.js";
import webGLConstantToGlslType from "../Core/webGLConstantToGlslType.js";
import addToArray from "../ThirdParty/GltfPipeline/addToArray.js";
import ForEach from "../ThirdParty/GltfPipeline/ForEach.js";
import hasExtension from "../ThirdParty/GltfPipeline/hasExtension.js";
import ModelUtility from "./ModelUtility.js";
/**
* @private
*/
function processPbrMaterials(gltf, options) {
options = defaultValue(options, defaultValue.EMPTY_OBJECT);
// No need to create new techniques if they already exist,
// the shader should handle these values
if (hasExtension(gltf, "KHR_techniques_webgl")) {
return gltf;
}
// All materials in glTF are PBR by default,
// so we should apply PBR unless no materials are found.
if (!defined(gltf.materials) || gltf.materials.length === 0) {
return gltf;
}
if (!defined(gltf.extensions)) {
gltf.extensions = {};
}
if (!defined(gltf.extensionsUsed)) {
gltf.extensionsUsed = [];
}
if (!defined(gltf.extensionsRequired)) {
gltf.extensionsRequired = [];
}
gltf.extensions.KHR_techniques_webgl = {
programs: [],
shaders: [],
techniques: [],
};
gltf.extensionsUsed.push("KHR_techniques_webgl");
gltf.extensionsRequired.push("KHR_techniques_webgl");
var primitiveByMaterial = ModelUtility.splitIncompatibleMaterials(gltf);
ForEach.material(gltf, function (material, materialIndex) {
var generatedMaterialValues = {};
var technique = generateTechnique(
gltf,
material,
materialIndex,
generatedMaterialValues,
primitiveByMaterial,
options
);
if (!defined(material.extensions)) {
material.extensions = {};
}
material.extensions.KHR_techniques_webgl = {
values: generatedMaterialValues,
technique: technique,
};
});
// If any primitives have semantics that aren't declared in the generated
// shaders, we want to preserve them.
ModelUtility.ensureSemanticExistence(gltf);
return gltf;
}
function isSpecularGlossinessMaterial(material) {
return (
defined(material.extensions) &&
defined(material.extensions.KHR_materials_pbrSpecularGlossiness)
);
}
function addTextureCoordinates(
gltf,
textureName,
generatedMaterialValues,
defaultTexCoord,
result
) {
var texCoord;
var texInfo = generatedMaterialValues[textureName];
if (defined(texInfo) && defined(texInfo.texCoord) && texInfo.texCoord === 1) {
defaultTexCoord = defaultTexCoord.replace("0", "1");
}
if (defined(generatedMaterialValues[textureName + "Offset"])) {
texCoord = textureName + "Coord";
result.fragmentShaderMain +=
" vec2 " +
texCoord +
" = computeTexCoord(" +
defaultTexCoord +
", " +
textureName +
"Offset, " +
textureName +
"Rotation, " +
textureName +
"Scale);\n";
} else {
texCoord = defaultTexCoord;
}
return texCoord;
}
var DEFAULT_TEXTURE_OFFSET = [0.0, 0.0];
var DEFAULT_TEXTURE_ROTATION = [0.0];
var DEFAULT_TEXTURE_SCALE = [1.0, 1.0];
function handleKHRTextureTransform(
parameterName,
value,
generatedMaterialValues
) {
if (
parameterName.indexOf("Texture") === -1 ||
!defined(value.extensions) ||
!defined(value.extensions.KHR_texture_transform)
) {
return;
}
var uniformName = "u_" + parameterName;
var extension = value.extensions.KHR_texture_transform;
generatedMaterialValues[uniformName + "Offset"] = defaultValue(
extension.offset,
DEFAULT_TEXTURE_OFFSET
);
generatedMaterialValues[uniformName + "Rotation"] = defaultValue(
extension.rotation,
DEFAULT_TEXTURE_ROTATION
);
generatedMaterialValues[uniformName + "Scale"] = defaultValue(
extension.scale,
DEFAULT_TEXTURE_SCALE
);
if (defined(value.texCoord) && defined(extension.texCoord)) {
generatedMaterialValues[uniformName].texCoord = extension.texCoord;
}
}
function generateTechnique(
gltf,
material,
materialIndex,
generatedMaterialValues,
primitiveByMaterial,
options
) {
var addBatchIdToGeneratedShaders = defaultValue(
options.addBatchIdToGeneratedShaders,
false
);
var techniquesWebgl = gltf.extensions.KHR_techniques_webgl;
var techniques = techniquesWebgl.techniques;
var shaders = techniquesWebgl.shaders;
var programs = techniquesWebgl.programs;
var useSpecGloss = isSpecularGlossinessMaterial(material);
var uniformName;
var parameterName;
var value;
var pbrMetallicRoughness = material.pbrMetallicRoughness;
if (defined(pbrMetallicRoughness) && !useSpecGloss) {
for (parameterName in pbrMetallicRoughness) {
if (pbrMetallicRoughness.hasOwnProperty(parameterName)) {
value = pbrMetallicRoughness[parameterName];
uniformName = "u_" + parameterName;
generatedMaterialValues[uniformName] = value;
handleKHRTextureTransform(
parameterName,
value,
generatedMaterialValues
);
}
}
}
if (useSpecGloss) {
var pbrSpecularGlossiness =
material.extensions.KHR_materials_pbrSpecularGlossiness;
for (parameterName in pbrSpecularGlossiness) {
if (pbrSpecularGlossiness.hasOwnProperty(parameterName)) {
value = pbrSpecularGlossiness[parameterName];
uniformName = "u_" + parameterName;
generatedMaterialValues[uniformName] = value;
handleKHRTextureTransform(
parameterName,
value,
generatedMaterialValues
);
}
}
}
for (var additional in material) {
if (
material.hasOwnProperty(additional) &&
(additional.indexOf("Texture") >= 0 || additional.indexOf("Factor") >= 0)
) {
value = material[additional];
uniformName = "u_" + additional;
generatedMaterialValues[uniformName] = value;
handleKHRTextureTransform(additional, value, generatedMaterialValues);
}
}
var vertexShader = "precision highp float;\n";
var fragmentShader = "precision highp float;\n";
var skin;
if (defined(gltf.skins)) {
skin = gltf.skins[0];
}
var joints = defined(skin) ? skin.joints : [];
var jointCount = joints.length;
var primitiveInfo = primitiveByMaterial[materialIndex];
var skinningInfo;
var hasSkinning = false;
var hasVertexColors = false;
var hasMorphTargets = false;
var hasNormals = false;
var hasTangents = false;
var hasTexCoords = false;
var hasTexCoord1 = false;
var hasOutline = false;
var isUnlit = false;
if (defined(primitiveInfo)) {
skinningInfo = primitiveInfo.skinning;
hasSkinning = skinningInfo.skinned && joints.length > 0;
hasVertexColors = primitiveInfo.hasVertexColors;
hasMorphTargets = primitiveInfo.hasMorphTargets;
hasNormals = primitiveInfo.hasNormals;
hasTangents = primitiveInfo.hasTangents;
hasTexCoords = primitiveInfo.hasTexCoords;
hasTexCoord1 = primitiveInfo.hasTexCoord1;
hasOutline = primitiveInfo.hasOutline;
}
var morphTargets;
if (hasMorphTargets) {
ForEach.mesh(gltf, function (mesh) {
ForEach.meshPrimitive(mesh, function (primitive) {
if (primitive.material === materialIndex) {
var targets = primitive.targets;
if (defined(targets)) {
morphTargets = targets;
}
}
});
});
}
// Add techniques
var techniqueUniforms = {
// Add matrices
u_modelViewMatrix: {
semantic: hasExtension(gltf, "CESIUM_RTC")
? "CESIUM_RTC_MODELVIEW"
: "MODELVIEW",
type: WebGLConstants.FLOAT_MAT4,
},
u_projectionMatrix: {
semantic: "PROJECTION",
type: WebGLConstants.FLOAT_MAT4,
},
};
if (
defined(material.extensions) &&
defined(material.extensions.KHR_materials_unlit)
) {
isUnlit = true;
}
if (hasNormals) {
techniqueUniforms.u_normalMatrix = {
semantic: "MODELVIEWINVERSETRANSPOSE",
type: WebGLConstants.FLOAT_MAT3,
};
}
if (hasSkinning) {
techniqueUniforms.u_jointMatrix = {
count: jointCount,
semantic: "JOINTMATRIX",
type: WebGLConstants.FLOAT_MAT4,
};
}
if (hasMorphTargets) {
techniqueUniforms.u_morphWeights = {
count: morphTargets.length,
semantic: "MORPHWEIGHTS",
type: WebGLConstants.FLOAT,
};
}
var alphaMode = material.alphaMode;
if (defined(alphaMode) && alphaMode === "MASK") {
techniqueUniforms.u_alphaCutoff = {
semantic: "ALPHACUTOFF",
type: WebGLConstants.FLOAT,
};
}
// Add material values
for (uniformName in generatedMaterialValues) {
if (generatedMaterialValues.hasOwnProperty(uniformName)) {
techniqueUniforms[uniformName] = {
type: getPBRValueType(uniformName),
};
}
}
var baseColorUniform = defaultValue(
techniqueUniforms.u_baseColorTexture,
techniqueUniforms.u_baseColorFactor
);
if (defined(baseColorUniform)) {
baseColorUniform.semantic = "_3DTILESDIFFUSE";
}
// Add uniforms to shaders
for (uniformName in techniqueUniforms) {
if (techniqueUniforms.hasOwnProperty(uniformName)) {
var uniform = techniqueUniforms[uniformName];
var arraySize = defined(uniform.count) ? "[" + uniform.count + "]" : "";
if (
(uniform.type !== WebGLConstants.FLOAT_MAT3 &&
uniform.type !== WebGLConstants.FLOAT_MAT4 &&
uniformName !== "u_morphWeights") ||
uniform.useInFragment
) {
fragmentShader +=
"uniform " +
webGLConstantToGlslType(uniform.type) +
" " +
uniformName +
arraySize +
";\n";
delete uniform.useInFragment;
} else {
vertexShader +=
"uniform " +
webGLConstantToGlslType(uniform.type) +
" " +
uniformName +
arraySize +
";\n";
}
}
}
if (hasOutline) {
fragmentShader += "uniform sampler2D u_outlineTexture;\n";
}
// Add attributes with semantics
var vertexShaderMain = "";
if (hasSkinning) {
vertexShaderMain +=
" mat4 skinMatrix =\n" +
" a_weight.x * u_jointMatrix[int(a_joint.x)] +\n" +
" a_weight.y * u_jointMatrix[int(a_joint.y)] +\n" +
" a_weight.z * u_jointMatrix[int(a_joint.z)] +\n" +
" a_weight.w * u_jointMatrix[int(a_joint.w)];\n";
}
// Add position always
var techniqueAttributes = {
a_position: {
semantic: "POSITION",
},
};
if (hasOutline) {
techniqueAttributes.a_outlineCoordinates = {
semantic: "_OUTLINE_COORDINATES",
};
}
vertexShader += "attribute vec3 a_position;\n";
if (hasNormals) {
vertexShader += "varying vec3 v_positionEC;\n";
}
if (hasOutline) {
vertexShader += "attribute vec3 a_outlineCoordinates;\n";
vertexShader += "varying vec3 v_outlineCoordinates;\n";
}
// Morph Target Weighting
vertexShaderMain += " vec3 weightedPosition = a_position;\n";
if (hasNormals) {
vertexShaderMain += " vec3 weightedNormal = a_normal;\n";
}
if (hasTangents) {
vertexShaderMain += " vec4 weightedTangent = a_tangent;\n";
}
if (hasMorphTargets) {
for (var k = 0; k < morphTargets.length; k++) {
var targetAttributes = morphTargets[k];
for (var targetAttribute in targetAttributes) {
if (
targetAttributes.hasOwnProperty(targetAttribute) &&
targetAttribute !== "extras"
) {
var attributeName = "a_" + targetAttribute + "_" + k;
techniqueAttributes[attributeName] = {
semantic: targetAttribute + "_" + k,
};
vertexShader += "attribute vec3 " + attributeName + ";\n";
if (targetAttribute === "POSITION") {
vertexShaderMain +=
" weightedPosition += u_morphWeights[" +
k +
"] * " +
attributeName +
";\n";
} else if (targetAttribute === "NORMAL") {
vertexShaderMain +=
" weightedNormal += u_morphWeights[" +
k +
"] * " +
attributeName +
";\n";
} else if (hasTangents && targetAttribute === "TANGENT") {
vertexShaderMain +=
" weightedTangent.xyz += u_morphWeights[" +
k +
"] * " +
attributeName +
";\n";
}
}
}
}
}
// Final position computation
if (hasSkinning) {
vertexShaderMain +=
" vec4 position = skinMatrix * vec4(weightedPosition, 1.0);\n";
} else {
vertexShaderMain += " vec4 position = vec4(weightedPosition, 1.0);\n";
}
vertexShaderMain += " position = u_modelViewMatrix * position;\n";
if (hasNormals) {
vertexShaderMain += " v_positionEC = position.xyz;\n";
}
vertexShaderMain += " gl_Position = u_projectionMatrix * position;\n";
if (hasOutline) {
vertexShaderMain += " v_outlineCoordinates = a_outlineCoordinates;\n";
}
// Final normal computation
if (hasNormals) {
techniqueAttributes.a_normal = {
semantic: "NORMAL",
};
vertexShader += "attribute vec3 a_normal;\n";
if (!isUnlit) {
vertexShader += "varying vec3 v_normal;\n";
if (hasSkinning) {
vertexShaderMain +=
" v_normal = u_normalMatrix * mat3(skinMatrix) * weightedNormal;\n";
} else {
vertexShaderMain += " v_normal = u_normalMatrix * weightedNormal;\n";
}
fragmentShader += "varying vec3 v_normal;\n";
}
fragmentShader += "varying vec3 v_positionEC;\n";
}
// Read tangents if available
if (hasTangents) {
techniqueAttributes.a_tangent = {
semantic: "TANGENT",
};
vertexShader += "attribute vec4 a_tangent;\n";
vertexShader += "varying vec4 v_tangent;\n";
vertexShaderMain +=
" v_tangent.xyz = u_normalMatrix * weightedTangent.xyz;\n";
vertexShaderMain += " v_tangent.w = weightedTangent.w;\n";
fragmentShader += "varying vec4 v_tangent;\n";
}
if (hasOutline) {
fragmentShader += "varying vec3 v_outlineCoordinates;\n";
}
var fragmentShaderMain = "";
// Add texture coordinates if the material uses them
var v_texCoord;
var normalTexCoord;
var baseColorTexCoord;
var specularGlossinessTexCoord;
var diffuseTexCoord;
var metallicRoughnessTexCoord;
var occlusionTexCoord;
var emissiveTexCoord;
if (hasTexCoords) {
techniqueAttributes.a_texcoord_0 = {
semantic: "TEXCOORD_0",
};
v_texCoord = "v_texcoord_0";
vertexShader += "attribute vec2 a_texcoord_0;\n";
vertexShader += "varying vec2 " + v_texCoord + ";\n";
vertexShaderMain += " " + v_texCoord + " = a_texcoord_0;\n";
fragmentShader += "varying vec2 " + v_texCoord + ";\n";
if (hasTexCoord1) {
techniqueAttributes.a_texcoord_1 = {
semantic: "TEXCOORD_1",
};
var v_texCoord1 = v_texCoord.replace("0", "1");
vertexShader += "attribute vec2 a_texcoord_1;\n";
vertexShader += "varying vec2 " + v_texCoord1 + ";\n";
vertexShaderMain += " " + v_texCoord1 + " = a_texcoord_1;\n";
fragmentShader += "varying vec2 " + v_texCoord1 + ";\n";
}
var result = {
fragmentShaderMain: fragmentShaderMain,
};
normalTexCoord = addTextureCoordinates(
gltf,
"u_normalTexture",
generatedMaterialValues,
v_texCoord,
result
);
baseColorTexCoord = addTextureCoordinates(
gltf,
"u_baseColorTexture",
generatedMaterialValues,
v_texCoord,
result
);
specularGlossinessTexCoord = addTextureCoordinates(
gltf,
"u_specularGlossinessTexture",
generatedMaterialValues,
v_texCoord,
result
);
diffuseTexCoord = addTextureCoordinates(
gltf,
"u_diffuseTexture",
generatedMaterialValues,
v_texCoord,
result
);
metallicRoughnessTexCoord = addTextureCoordinates(
gltf,
"u_metallicRoughnessTexture",
generatedMaterialValues,
v_texCoord,
result
);
occlusionTexCoord = addTextureCoordinates(
gltf,
"u_occlusionTexture",
generatedMaterialValues,
v_texCoord,
result
);
emissiveTexCoord = addTextureCoordinates(
gltf,
"u_emissiveTexture",
generatedMaterialValues,
v_texCoord,
result
);
fragmentShaderMain = result.fragmentShaderMain;
}
// Add skinning information if available
if (hasSkinning) {
techniqueAttributes.a_joint = {
semantic: "JOINTS_0",
};
techniqueAttributes.a_weight = {
semantic: "WEIGHTS_0",
};
vertexShader += "attribute vec4 a_joint;\n";
vertexShader += "attribute vec4 a_weight;\n";
}
if (hasVertexColors) {
techniqueAttributes.a_vertexColor = {
semantic: "COLOR_0",
};
vertexShader += "attribute vec4 a_vertexColor;\n";
vertexShader += "varying vec4 v_vertexColor;\n";
vertexShaderMain += " v_vertexColor = a_vertexColor;\n";
fragmentShader += "varying vec4 v_vertexColor;\n";
}
if (addBatchIdToGeneratedShaders) {
techniqueAttributes.a_batchId = {
semantic: "_BATCHID",
};
vertexShader += "attribute float a_batchId;\n";
}
vertexShader += "void main(void) \n{\n";
vertexShader += vertexShaderMain;
vertexShader += "}\n";
// Fragment shader lighting
if (hasNormals && !isUnlit) {
fragmentShader += "const float M_PI = 3.141592653589793;\n";
fragmentShader +=
"vec3 lambertianDiffuse(vec3 diffuseColor) \n" +
"{\n" +
" return diffuseColor / M_PI;\n" +
"}\n\n";
fragmentShader +=
"vec3 fresnelSchlick2(vec3 f0, vec3 f90, float VdotH) \n" +
"{\n" +
" return f0 + (f90 - f0) * pow(clamp(1.0 - VdotH, 0.0, 1.0), 5.0);\n" +
"}\n\n";
fragmentShader +=
"vec3 fresnelSchlick(float metalness, float VdotH) \n" +
"{\n" +
" return metalness + (vec3(1.0) - metalness) * pow(1.0 - VdotH, 5.0);\n" +
"}\n\n";
fragmentShader +=
"float smithVisibilityG1(float NdotV, float roughness) \n" +
"{\n" +
" float k = (roughness + 1.0) * (roughness + 1.0) / 8.0;\n" +
" return NdotV / (NdotV * (1.0 - k) + k);\n" +
"}\n\n";
fragmentShader +=
"float smithVisibilityGGX(float roughness, float NdotL, float NdotV) \n" +
"{\n" +
" return smithVisibilityG1(NdotL, roughness) * smithVisibilityG1(NdotV, roughness);\n" +
"}\n\n";
fragmentShader +=
"float GGX(float roughness, float NdotH) \n" +
"{\n" +
" float roughnessSquared = roughness * roughness;\n" +
" float f = (NdotH * roughnessSquared - NdotH) * NdotH + 1.0;\n" +
" return roughnessSquared / (M_PI * f * f);\n" +
"}\n\n";
}
fragmentShader +=
"vec3 SRGBtoLINEAR3(vec3 srgbIn) \n" +
"{\n" +
" return pow(srgbIn, vec3(2.2));\n" +
"}\n\n";
fragmentShader +=
"vec4 SRGBtoLINEAR4(vec4 srgbIn) \n" +
"{\n" +
" vec3 linearOut = pow(srgbIn.rgb, vec3(2.2));\n" +
" return vec4(linearOut, srgbIn.a);\n" +
"}\n\n";
fragmentShader +=
"vec3 applyTonemapping(vec3 linearIn) \n" +
"{\n" +
"#ifndef HDR \n" +
" return czm_acesTonemapping(linearIn);\n" +
"#else \n" +
" return linearIn;\n" +
"#endif \n" +
"}\n\n";
fragmentShader +=
"vec3 LINEARtoSRGB(vec3 linearIn) \n" +
"{\n" +
"#ifndef HDR \n" +
" return pow(linearIn, vec3(1.0/2.2));\n" +
"#else \n" +
" return linearIn;\n" +
"#endif \n" +
"}\n\n";
fragmentShader +=
"vec2 computeTexCoord(vec2 texCoords, vec2 offset, float rotation, vec2 scale) \n" +
"{\n" +
" rotation = -rotation; \n" +
" mat3 transform = mat3(\n" +
" cos(rotation) * scale.x, sin(rotation) * scale.x, 0.0, \n" +
" -sin(rotation) * scale.y, cos(rotation) * scale.y, 0.0, \n" +
" offset.x, offset.y, 1.0); \n" +
" vec2 transformedTexCoords = (transform * vec3(fract(texCoords), 1.0)).xy; \n" +
" return transformedTexCoords; \n" +
"}\n\n";
fragmentShader += "#ifdef USE_IBL_LIGHTING \n";
fragmentShader += "uniform vec2 gltf_iblFactor; \n";
fragmentShader += "#endif \n";
fragmentShader += "#ifdef USE_CUSTOM_LIGHT_COLOR \n";
fragmentShader += "uniform vec3 gltf_lightColor; \n";
fragmentShader += "#endif \n";
fragmentShader += "void main(void) \n{\n";
fragmentShader += fragmentShaderMain;
// Add normal mapping to fragment shader
if (hasNormals && !isUnlit) {
fragmentShader += " vec3 ng = normalize(v_normal);\n";
fragmentShader +=
" vec3 positionWC = vec3(czm_inverseView * vec4(v_positionEC, 1.0));\n";
if (defined(generatedMaterialValues.u_normalTexture)) {
if (hasTangents) {
// Read tangents from varying
fragmentShader += " vec3 t = normalize(v_tangent.xyz);\n";
fragmentShader +=
" vec3 b = normalize(cross(ng, t) * v_tangent.w);\n";
fragmentShader += " mat3 tbn = mat3(t, b, ng);\n";
fragmentShader +=
" vec3 n = texture2D(u_normalTexture, " +
normalTexCoord +
").rgb;\n";
fragmentShader += " n = normalize(tbn * (2.0 * n - 1.0));\n";
} else {
// Add standard derivatives extension
fragmentShader =
"#ifdef GL_OES_standard_derivatives\n" +
"#extension GL_OES_standard_derivatives : enable\n" +
"#endif\n" +
fragmentShader;
// Compute tangents
fragmentShader += "#ifdef GL_OES_standard_derivatives\n";
fragmentShader += " vec3 pos_dx = dFdx(v_positionEC);\n";
fragmentShader += " vec3 pos_dy = dFdy(v_positionEC);\n";
fragmentShader +=
" vec3 tex_dx = dFdx(vec3(" + normalTexCoord + ",0.0));\n";
fragmentShader +=
" vec3 tex_dy = dFdy(vec3(" + normalTexCoord + ",0.0));\n";
fragmentShader +=
" vec3 t = (tex_dy.t * pos_dx - tex_dx.t * pos_dy) / (tex_dx.s * tex_dy.t - tex_dy.s * tex_dx.t);\n";
fragmentShader += " t = normalize(t - ng * dot(ng, t));\n";
fragmentShader += " vec3 b = normalize(cross(ng, t));\n";
fragmentShader += " mat3 tbn = mat3(t, b, ng);\n";
fragmentShader +=
" vec3 n = texture2D(u_normalTexture, " +
normalTexCoord +
").rgb;\n";
fragmentShader += " n = normalize(tbn * (2.0 * n - 1.0));\n";
fragmentShader += "#else\n";
fragmentShader += " vec3 n = ng;\n";
fragmentShader += "#endif\n";
}
} else {
fragmentShader += " vec3 n = ng;\n";
}
if (material.doubleSided) {
fragmentShader += " if (czm_backFacing())\n";
fragmentShader += " {\n";
fragmentShader += " n = -n;\n";
fragmentShader += " }\n";
}
}
// Add base color to fragment shader
if (defined(generatedMaterialValues.u_baseColorTexture)) {
fragmentShader +=
" vec4 baseColorWithAlpha = SRGBtoLINEAR4(texture2D(u_baseColorTexture, " +
baseColorTexCoord +
"));\n";
if (defined(generatedMaterialValues.u_baseColorFactor)) {
fragmentShader += " baseColorWithAlpha *= u_baseColorFactor;\n";
}
} else if (defined(generatedMaterialValues.u_baseColorFactor)) {
fragmentShader += " vec4 baseColorWithAlpha = u_baseColorFactor;\n";
} else {
fragmentShader += " vec4 baseColorWithAlpha = vec4(1.0);\n";
}
if (hasVertexColors) {
fragmentShader += " baseColorWithAlpha *= v_vertexColor;\n";
}
fragmentShader += " vec3 baseColor = baseColorWithAlpha.rgb;\n";
if (hasNormals && !isUnlit) {
if (useSpecGloss) {
if (defined(generatedMaterialValues.u_specularGlossinessTexture)) {
fragmentShader +=
" vec4 specularGlossiness = SRGBtoLINEAR4(texture2D(u_specularGlossinessTexture, " +
specularGlossinessTexCoord +
"));\n";
fragmentShader += " vec3 specular = specularGlossiness.rgb;\n";
fragmentShader += " float glossiness = specularGlossiness.a;\n";
if (defined(generatedMaterialValues.u_specularFactor)) {
fragmentShader += " specular *= u_specularFactor;\n";
}
if (defined(generatedMaterialValues.u_glossinessFactor)) {
fragmentShader += " glossiness *= u_glossinessFactor;\n";
}
} else {
if (defined(generatedMaterialValues.u_specularFactor)) {
fragmentShader +=
" vec3 specular = clamp(u_specularFactor, vec3(0.0), vec3(1.0));\n";
} else {
fragmentShader += " vec3 specular = vec3(1.0);\n";
}
if (defined(generatedMaterialValues.u_glossinessFactor)) {
fragmentShader +=
" float glossiness = clamp(u_glossinessFactor, 0.0, 1.0);\n";
} else {
fragmentShader += " float glossiness = 1.0;\n";
}
}
if (defined(generatedMaterialValues.u_diffuseTexture)) {
fragmentShader +=
" vec4 diffuse = SRGBtoLINEAR4(texture2D(u_diffuseTexture, " +
diffuseTexCoord +
"));\n";
if (defined(generatedMaterialValues.u_diffuseFactor)) {
fragmentShader += " diffuse *= u_diffuseFactor;\n";
}
} else if (defined(generatedMaterialValues.u_diffuseFactor)) {
fragmentShader +=
" vec4 diffuse = clamp(u_diffuseFactor, vec4(0.0), vec4(1.0));\n";
} else {
fragmentShader += " vec4 diffuse = vec4(1.0);\n";
}
} else if (defined(generatedMaterialValues.u_metallicRoughnessTexture)) {
fragmentShader +=
" vec3 metallicRoughness = texture2D(u_metallicRoughnessTexture, " +
metallicRoughnessTexCoord +
").rgb;\n";
fragmentShader +=
" float metalness = clamp(metallicRoughness.b, 0.0, 1.0);\n";
fragmentShader +=
" float roughness = clamp(metallicRoughness.g, 0.04, 1.0);\n";
if (defined(generatedMaterialValues.u_metallicFactor)) {
fragmentShader += " metalness *= u_metallicFactor;\n";
}
if (defined(generatedMaterialValues.u_roughnessFactor)) {
fragmentShader += " roughness *= u_roughnessFactor;\n";
}
} else {
if (defined(generatedMaterialValues.u_metallicFactor)) {
fragmentShader +=
" float metalness = clamp(u_metallicFactor, 0.0, 1.0);\n";
} else {
fragmentShader += " float metalness = 1.0;\n";
}
if (defined(generatedMaterialValues.u_roughnessFactor)) {
fragmentShader +=
" float roughness = clamp(u_roughnessFactor, 0.04, 1.0);\n";
} else {
fragmentShader += " float roughness = 1.0;\n";
}
}
fragmentShader += " vec3 v = -normalize(v_positionEC);\n";
// Generate fragment shader's lighting block
fragmentShader += "#ifndef USE_CUSTOM_LIGHT_COLOR \n";
fragmentShader += " vec3 lightColorHdr = czm_lightColorHdr;\n";
fragmentShader += "#else \n";
fragmentShader += " vec3 lightColorHdr = gltf_lightColor;\n";
fragmentShader += "#endif \n";
fragmentShader += " vec3 l = normalize(czm_lightDirectionEC);\n";
fragmentShader += " vec3 h = normalize(v + l);\n";
fragmentShader += " float NdotL = clamp(dot(n, l), 0.001, 1.0);\n";
fragmentShader += " float NdotV = abs(dot(n, v)) + 0.001;\n";
fragmentShader += " float NdotH = clamp(dot(n, h), 0.0, 1.0);\n";
fragmentShader += " float LdotH = clamp(dot(l, h), 0.0, 1.0);\n";
fragmentShader += " float VdotH = clamp(dot(v, h), 0.0, 1.0);\n";
fragmentShader += " vec3 f0 = vec3(0.04);\n";
// Whether the material uses metallic-roughness or specular-glossiness changes how the BRDF inputs are computed.
// It does not change the implementation of the BRDF itself.
if (useSpecGloss) {
fragmentShader += " float roughness = 1.0 - glossiness;\n";
fragmentShader +=
" vec3 diffuseColor = diffuse.rgb * (1.0 - max(max(specular.r, specular.g), specular.b));\n";
fragmentShader += " vec3 specularColor = specular;\n";
} else {
fragmentShader +=
" vec3 diffuseColor = baseColor * (1.0 - metalness) * (1.0 - f0);\n";
fragmentShader +=
" vec3 specularColor = mix(f0, baseColor, metalness);\n";
}
fragmentShader += " float alpha = roughness * roughness;\n";
fragmentShader +=
" float reflectance = max(max(specularColor.r, specularColor.g), specularColor.b);\n";
fragmentShader +=
" vec3 r90 = vec3(clamp(reflectance * 25.0, 0.0, 1.0));\n";
fragmentShader += " vec3 r0 = specularColor.rgb;\n";
fragmentShader += " vec3 F = fresnelSchlick2(r0, r90, VdotH);\n";
fragmentShader +=
" float G = smithVisibilityGGX(alpha, NdotL, NdotV);\n";
fragmentShader += " float D = GGX(alpha, NdotH);\n";
fragmentShader +=
" vec3 diffuseContribution = (1.0 - F) * lambertianDiffuse(diffuseColor);\n";
fragmentShader +=
" vec3 specularContribution = F * G * D / (4.0 * NdotL * NdotV);\n";
fragmentShader +=
" vec3 color = NdotL * lightColorHdr * (diffuseContribution + specularContribution);\n";
// Use the procedural IBL if there are no environment maps
fragmentShader +=
"#if defined(USE_IBL_LIGHTING) && !defined(DIFFUSE_IBL) && !defined(SPECULAR_IBL) \n";
fragmentShader +=
" vec3 r = normalize(czm_inverseViewRotation * normalize(reflect(v, n)));\n";
// Figure out if the reflection vector hits the ellipsoid
fragmentShader += " float vertexRadius = length(positionWC);\n";
fragmentShader +=
" float horizonDotNadir = 1.0 - min(1.0, czm_ellipsoidRadii.x / vertexRadius);\n";
fragmentShader +=
" float reflectionDotNadir = dot(r, normalize(positionWC));\n";
// Flipping the X vector is a cheap way to get the inverse of czm_temeToPseudoFixed, since that's a rotation about Z.
fragmentShader += " r.x = -r.x;\n";
fragmentShader += " r = -normalize(czm_temeToPseudoFixed * r);\n";
fragmentShader += " r.x = -r.x;\n";
fragmentShader += " float inverseRoughness = 1.04 - roughness;\n";
fragmentShader += " inverseRoughness *= inverseRoughness;\n";
fragmentShader +=
" vec3 sceneSkyBox = textureCube(czm_environmentMap, r).rgb * inverseRoughness;\n";
fragmentShader += " float atmosphereHeight = 0.05;\n";
fragmentShader +=
" float blendRegionSize = 0.1 * ((1.0 - inverseRoughness) * 8.0 + 1.1 - horizonDotNadir);\n";
fragmentShader += " float blendRegionOffset = roughness * -1.0;\n";
fragmentShader +=
" float farAboveHorizon = clamp(horizonDotNadir - blendRegionSize * 0.5 + blendRegionOffset, 1.0e-10 - blendRegionSize, 0.99999);\n";
fragmentShader +=
" float aroundHorizon = clamp(horizonDotNadir + blendRegionSize * 0.5, 1.0e-10 - blendRegionSize, 0.99999);\n";
fragmentShader +=
" float farBelowHorizon = clamp(horizonDotNadir + blendRegionSize * 1.5, 1.0e-10 - blendRegionSize, 0.99999);\n";
fragmentShader +=
" float smoothstepHeight = smoothstep(0.0, atmosphereHeight, horizonDotNadir);\n";
fragmentShader +=
" vec3 belowHorizonColor = mix(vec3(0.1, 0.15, 0.25), vec3(0.4, 0.7, 0.9), smoothstepHeight);\n";
fragmentShader += " vec3 nadirColor = belowHorizonColor * 0.5;\n";
fragmentShader +=
" vec3 aboveHorizonColor = mix(vec3(0.9, 1.0, 1.2), belowHorizonColor, roughness * 0.5);\n";
fragmentShader +=
" vec3 blueSkyColor = mix(vec3(0.18, 0.26, 0.48), aboveHorizonColor, reflectionDotNadir * inverseRoughness * 0.5 + 0.75);\n";
fragmentShader +=
" vec3 zenithColor = mix(blueSkyColor, sceneSkyBox, smoothstepHeight);\n";
fragmentShader += " vec3 blueSkyDiffuseColor = vec3(0.7, 0.85, 0.9);\n";
fragmentShader +=
" float diffuseIrradianceFromEarth = (1.0 - horizonDotNadir) * (reflectionDotNadir * 0.25 + 0.75) * smoothstepHeight;\n";
fragmentShader +=
" float diffuseIrradianceFromSky = (1.0 - smoothstepHeight) * (1.0 - (reflectionDotNadir * 0.25 + 0.25));\n";
fragmentShader +=
" vec3 diffuseIrradiance = blueSkyDiffuseColor * clamp(diffuseIrradianceFromEarth + diffuseIrradianceFromSky, 0.0, 1.0);\n";
fragmentShader +=
" float notDistantRough = (1.0 - horizonDotNadir * roughness * 0.8);\n";
fragmentShader +=
" vec3 specularIrradiance = mix(zenithColor, aboveHorizonColor, smoothstep(farAboveHorizon, aroundHorizon, reflectionDotNadir) * notDistantRough);\n";
fragmentShader +=
" specularIrradiance = mix(specularIrradiance, belowHorizonColor, smoothstep(aroundHorizon, farBelowHorizon, reflectionDotNadir) * inverseRoughness);\n";
fragmentShader +=
" specularIrradiance = mix(specularIrradiance, nadirColor, smoothstep(farBelowHorizon, 1.0, reflectionDotNadir) * inverseRoughness);\n";
// Luminance model from page 40 of http://silviojemma.com/public/papers/lighting/spherical-harmonic-lighting.pdf
fragmentShader += "#ifdef USE_SUN_LUMINANCE \n";
// Angle between sun and zenith
fragmentShader +=
" float LdotZenith = clamp(dot(normalize(czm_inverseViewRotation * l), normalize(positionWC * -1.0)), 0.001, 1.0);\n";
fragmentShader += " float S = acos(LdotZenith);\n";
// Angle between zenith and current pixel
fragmentShader +=
" float NdotZenith = clamp(dot(normalize(czm_inverseViewRotation * n), normalize(positionWC * -1.0)), 0.001, 1.0);\n";
// Angle between sun and current pixel
fragmentShader += " float gamma = acos(NdotL);\n";
fragmentShader +=
" float numerator = ((0.91 + 10.0 * exp(-3.0 * gamma) + 0.45 * pow(NdotL, 2.0)) * (1.0 - exp(-0.32 / NdotZenith)));\n";
fragmentShader +=
" float denominator = (0.91 + 10.0 * exp(-3.0 * S) + 0.45 * pow(LdotZenith,2.0)) * (1.0 - exp(-0.32));\n";
fragmentShader +=
" float luminance = gltf_luminanceAtZenith * (numerator / denominator);\n";
fragmentShader += "#endif \n";
fragmentShader +=
" vec2 brdfLut = texture2D(czm_brdfLut, vec2(NdotV, roughness)).rg;\n";
fragmentShader +=
" vec3 IBLColor = (diffuseIrradiance * diffuseColor * gltf_iblFactor.x) + (specularIrradiance * SRGBtoLINEAR3(specularColor * brdfLut.x + brdfLut.y) * gltf_iblFactor.y);\n";
fragmentShader +=
" float maximumComponent = max(max(lightColorHdr.x, lightColorHdr.y), lightColorHdr.z);\n";
fragmentShader +=
" vec3 lightColor = lightColorHdr / max(maximumComponent, 1.0);\n";
fragmentShader += " IBLColor *= lightColor;\n";
fragmentShader += "#ifdef USE_SUN_LUMINANCE \n";
fragmentShader += " color += IBLColor * luminance;\n";
fragmentShader += "#else \n";
fragmentShader += " color += IBLColor; \n";
fragmentShader += "#endif \n";
// Environment maps were provided, use them for IBL
fragmentShader += "#elif defined(DIFFUSE_IBL) || defined(SPECULAR_IBL) \n";
fragmentShader +=
" const mat3 yUpToZUp = mat3(-1.0, 0.0, 0.0, 0.0, 0.0, -1.0, 0.0, 1.0, 0.0); \n";
fragmentShader +=
" vec3 cubeDir = normalize(yUpToZUp * gltf_iblReferenceFrameMatrix * normalize(reflect(-v, n))); \n";
fragmentShader += "#ifdef DIFFUSE_IBL \n";
fragmentShader += "#ifdef CUSTOM_SPHERICAL_HARMONICS \n";
fragmentShader +=
" vec3 diffuseIrradiance = czm_sphericalHarmonics(cubeDir, gltf_sphericalHarmonicCoefficients); \n";
fragmentShader += "#else \n";
fragmentShader +=
" vec3 diffuseIrradiance = czm_sphericalHarmonics(cubeDir, czm_sphericalHarmonicCoefficients); \n";
fragmentShader += "#endif \n";
fragmentShader += "#else \n";
fragmentShader += " vec3 diffuseIrradiance = vec3(0.0); \n";
fragmentShader += "#endif \n";
fragmentShader += "#ifdef SPECULAR_IBL \n";
fragmentShader +=
" vec2 brdfLut = texture2D(czm_brdfLut, vec2(NdotV, roughness)).rg;\n";
fragmentShader += "#ifdef CUSTOM_SPECULAR_IBL \n";
fragmentShader +=
" vec3 specularIBL = czm_sampleOctahedralProjection(gltf_specularMap, gltf_specularMapSize, cubeDir, roughness * gltf_maxSpecularLOD, gltf_maxSpecularLOD);\n";
fragmentShader += "#else \n";
fragmentShader +=
" vec3 specularIBL = czm_sampleOctahedralProjection(czm_specularEnvironmentMaps, czm_specularEnvironmentMapSize, cubeDir, roughness * czm_specularEnvironmentMapsMaximumLOD, czm_specularEnvironmentMapsMaximumLOD);\n";
fragmentShader += "#endif \n";
fragmentShader += " specularIBL *= F * brdfLut.x + brdfLut.y;\n";
fragmentShader += "#else \n";
fragmentShader += " vec3 specularIBL = vec3(0.0); \n";
fragmentShader += "#endif \n";
fragmentShader +=
" color += diffuseIrradiance * diffuseColor + specularColor * specularIBL;\n";
fragmentShader += "#endif \n";
} else {
fragmentShader += " vec3 color = baseColor;\n";
}
// Ignore occlusion and emissive when unlit
if (!isUnlit) {
if (defined(generatedMaterialValues.u_occlusionTexture)) {
fragmentShader +=
" color *= texture2D(u_occlusionTexture, " +
occlusionTexCoord +
").r;\n";
}
if (defined(generatedMaterialValues.u_emissiveTexture)) {
fragmentShader +=
" vec3 emissive = SRGBtoLINEAR3(texture2D(u_emissiveTexture, " +
emissiveTexCoord +
").rgb);\n";
if (defined(generatedMaterialValues.u_emissiveFactor)) {
fragmentShader += " emissive *= u_emissiveFactor;\n";
}
fragmentShader += " color += emissive;\n";
} else if (defined(generatedMaterialValues.u_emissiveFactor)) {
fragmentShader += " color += u_emissiveFactor;\n";
}
}
if (!isUnlit) {
fragmentShader += " color = applyTonemapping(color);\n";
}
fragmentShader += " color = LINEARtoSRGB(color);\n";
if (hasOutline) {
fragmentShader += " float outlineness = max(\n";
fragmentShader +=
" texture2D(u_outlineTexture, vec2(v_outlineCoordinates.x, 0.5)).r,\n";
fragmentShader += " max(\n";
fragmentShader +=
" texture2D(u_outlineTexture, vec2(v_outlineCoordinates.y, 0.5)).r,\n";
fragmentShader +=
" texture2D(u_outlineTexture, vec2(v_outlineCoordinates.z, 0.5)).r));\n";
fragmentShader +=
" color = mix(color, vec3(0.0, 0.0, 0.0), outlineness);\n";
}
if (defined(alphaMode)) {
if (alphaMode === "MASK") {
fragmentShader += " if (baseColorWithAlpha.a < u_alphaCutoff) {\n";
fragmentShader += " discard;\n";
fragmentShader += " }\n";
fragmentShader += " gl_FragColor = vec4(color, 1.0);\n";
} else if (alphaMode === "BLEND") {
fragmentShader +=
" gl_FragColor = vec4(color, baseColorWithAlpha.a);\n";
} else {
fragmentShader += " gl_FragColor = vec4(color, 1.0);\n";
}
} else {
fragmentShader += " gl_FragColor = vec4(color, 1.0);\n";
}
fragmentShader += "}\n";
// Add shaders
var vertexShaderId = addToArray(shaders, {
type: WebGLConstants.VERTEX_SHADER,
extras: {
_pipeline: {
source: vertexShader,
extension: ".glsl",
},
},
});
var fragmentShaderId = addToArray(shaders, {
type: WebGLConstants.FRAGMENT_SHADER,
extras: {
_pipeline: {
source: fragmentShader,
extension: ".glsl",
},
},
});
// Add program
var programId = addToArray(programs, {
fragmentShader: fragmentShaderId,
vertexShader: vertexShaderId,
});
var techniqueId = addToArray(techniques, {
attributes: techniqueAttributes,
program: programId,
uniforms: techniqueUniforms,
});
return techniqueId;
}
function getPBRValueType(paramName) {
if (paramName.indexOf("Offset") !== -1) {
return WebGLConstants.FLOAT_VEC2;
} else if (paramName.indexOf("Rotation") !== -1) {
return WebGLConstants.FLOAT;
} else if (paramName.indexOf("Scale") !== -1) {
return WebGLConstants.FLOAT_VEC2;
} else if (paramName.indexOf("Texture") !== -1) {
return WebGLConstants.SAMPLER_2D;
}
switch (paramName) {
case "u_baseColorFactor":
return WebGLConstants.FLOAT_VEC4;
case "u_metallicFactor":
return WebGLConstants.FLOAT;
case "u_roughnessFactor":
return WebGLConstants.FLOAT;
case "u_emissiveFactor":
return WebGLConstants.FLOAT_VEC3;
// Specular Glossiness Types
case "u_diffuseFactor":
return WebGLConstants.FLOAT_VEC4;
case "u_specularFactor":
return WebGLConstants.FLOAT_VEC3;
case "u_glossinessFactor":
return WebGLConstants.FLOAT;
}
}
export default processPbrMaterials;