二十一，结合直射光和间接光绘制小球

走到这一步，可以说，将直接光和间接光都走完了，要把这些结合起来了。
与learn opengl中不同的是，预过滤环境贴图没有用Mipmap，而是把五个不同粗糙度的所有纹理都加进来。

osg::ref_ptr prefilterMap_0 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_0, 0);
osg::ref_ptr prefilterMap_1 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_1, 1);
osg::ref_ptr prefilterMap_2 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_2, 2);
osg::ref_ptr prefilterMap_3 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_3, 3);
osg::ref_ptr prefilterMap_4 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_4, 4);

osg::ref_ptr prefilter0Uniform = new osg::Uniform("prefilterMap0", 0);
osg::ref_ptr prefilter1Uniform = new osg::Uniform("prefilterMap1",1);
osg::ref_ptr prefilter2Uniform = new osg::Uniform("prefilterMap2", 2);
osg::ref_ptr prefilter3Uniform = new osg::Uniform("prefilterMap3", 3);
osg::ref_ptr prefilter4Uniform = new osg::Uniform("prefilterMap4", 4);
osg::ref_ptr tex0Uniform = new osg::Uniform("irradianceMap", 5);
osg::ref_ptr brdfLUTUniform = new osg::Uniform("brdfLUT", 6);

			stateset->addUniform(tex0Uniform);
			stateset->addUniform(brdfLUTUniform);
			stateset->addUniform(prefilter0Uniform);
			stateset->addUniform(prefilter1Uniform);
			stateset->addUniform(prefilter2Uniform);
			stateset->addUniform(prefilter3Uniform);
			stateset->addUniform(prefilter4Uniform);

			osg::ref_ptr stateset = geode->getOrCreateStateSet();
			stateset->setTextureAttributeAndModes(0, prefilterMap_0, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(1, prefilterMap_1, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(2, prefilterMap_2, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(3, prefilterMap_3, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(4, prefilterMap_4, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(5, irradianceTextureCubeMap, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(6, textureBRDFLUT, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);

代码如下：
//通过Liblas读取.las文件，并在osg中显示出来,用shader，先在片元着色器指定使用绿色
#include
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static const char * vertexShader_PBR =
{
“in vec3 aPos; \n”
“in vec3 aNormal; \n”
“varying vec3 WorldPos; \n”
“varying vec3 Normal; \n”
“uniform mat4 normalMatrix; \n”
“void main() \n”
“{ \n”
" WorldPos = aPos; \n"
" Normal = vec3(normalMatrix * vec4(aNormal,1.0)); \n"
" gl_Position = ftransform(); \n"
“}\n”
};

static const char *psShader_PBR =
{
“#version 330 core \n”
“out vec4 FragColor; \n”
“varying vec3 WorldPos; \n”
“varying vec3 Normal; \n”
“uniform vec3 albedo; \n”
“uniform float metallic; \n”
“uniform float roughness; \n”
“uniform float ao; \n”
//IBL
“uniform samplerCube irradianceMap;”
“uniform sampler2D brdfLUT; \n”
“uniform samplerCube prefilterMap0; \n”
“uniform samplerCube prefilterMap1; \n”
“uniform samplerCube prefilterMap2; \n”
“uniform samplerCube prefilterMap3; \n”
“uniform samplerCube prefilterMap4; \n”

"uniform vec3 lightPositions[4];																  \n"
"uniform vec3 lightColors[4];																	  \n"
"uniform vec3 camPos;																			  \n"
"const float PI = 3.14159265359;																  \n"
"float DistributionGGX(vec3 N, vec3 H, float roughness)											  \n"
"{																								  \n"
"	float a = roughness*roughness;																  \n"
"	float a2 = a*a;																				  \n"
"	float NdotH = max(dot(N, H), 0.0);															  \n"
"	float NdotH2 = NdotH*NdotH;																	  \n"
"	float nom = a2;																				  \n"
"	float denom = (NdotH2 * (a2 - 1.0) + 1.0);													  \n"
"	denom = PI * denom * denom;																	  \n"
"	return nom / denom;																			  \n"
"}																								  \n"
"float GeometrySchlickGGX(float NdotV, float roughness)											  \n"
"{																								  \n"
"	float r = (roughness + 1.0);																  \n"
"	float k = (r*r) / 8.0;																		  \n"
"	float nom = NdotV;																			  \n"
"	float denom = NdotV * (1.0 - k) + k;														  \n"
"	return nom / denom;																			  \n"
"}																								  \n"
"float GeometrySmith(vec3 N, vec3 V, vec3 L, float roughness)									  \n"
"{																								  \n"
"	float NdotV = max(dot(N, V), 0.0);															  \n"
"	float NdotL = max(dot(N, L), 0.0);															  \n"
"	float ggx2 = GeometrySchlickGGX(NdotV, roughness);											  \n"
"	float ggx1 = GeometrySchlickGGX(NdotL, roughness);											  \n"
"	return ggx1 * ggx2;																			  \n"
"}																								  \n"
"vec3 fresnelSchlick(float cosTheta, vec3 F0)													  \n"
"{																								  \n"
"	return F0 + (1.0 - F0) * pow(clamp(1.0 - cosTheta, 0.0, 1.0), 5.0);							  \n"
"}																								  \n"
"vec3 fresnelSchlickRoughness(float cosTheta, vec3 F0, float roughness)									  \n"
"{																										  \n"
"	return F0 + (max(vec3(1.0 - roughness), F0) - F0) * pow(clamp(1.0 - cosTheta, 0.0, 1.0), 5.0);		  \n"
"}																										  \n"
"void main()																						\n"
"{																									\n"
"	vec3 N = normalize(Normal);																		\n"
"	vec3 V = normalize(camPos - WorldPos);															\n"
" vec3 R = reflect(-V, N);\n"
"	vec3 F0 = vec3(0.04);																			\n"
"	F0 = mix(F0, albedo, metallic);																	\n"
"	vec3 Lo = vec3(0.0);																			\n"
"	for (int i = 0; i < 4; ++i)																		\n"
"	{																								\n"
"		vec3 L = normalize(lightPositions[i] - WorldPos);											\n"
"		vec3 H = normalize(V + L);																	\n"
"		float distance = length(lightPositions[i] - WorldPos);										\n"
"		float attenuation = 1.0 / (distance * distance);											\n"
"		vec3 radiance = lightColors[i] * attenuation;												\n"
"		float NDF = DistributionGGX(N, H, roughness);												\n"
"		float G = GeometrySmith(N, V, L, roughness);												\n"
"		vec3 F = fresnelSchlick(clamp(dot(H, V), 0.0, 1.0), F0);									\n"
"		vec3 numerator = NDF * G * F;																\n"
"		float denominator = 4.0 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0) + 0.0001; 				\n"
"		vec3 specular = numerator / denominator;													\n"
"		vec3 kS = F;																				\n"
"		vec3 kD = vec3(1.0) - kS;																	\n"
"		kD *= 1.0 - metallic;																		\n"
"		float NdotL = max(dot(N, L), 0.0);															\n"
"		Lo += (kD * albedo / PI + specular) * radiance * NdotL;  									\n"
"	}																								\n"
// ambient lighting (we now use IBL as the ambient term)
"vec3 F = fresnelSchlickRoughness(max(dot(N, V), 0.0), F0, roughness);							 \n"
"vec3 kS = F;																					 \n"
"vec3 kD = 1.0 - kS;"
"  kD *= 1.0 - metallic;	\n"
"vec3 irradiance = texture(irradianceMap, N).rgb;"
"vec3 diffuse = irradiance * albedo;"
// sample both the pre-filter map and the BRDF lut and combine them together as per the Split-Sum approximation to get the IBL specular part.
"const float MAX_REFLECTION_LOD = 4.0;																	  \n"
"float level = roughness * MAX_REFLECTION_LOD;\n"
"vec3 prefilteredColor = vec3(0,0,0);\n"
"if(level >= 4)\n"
"{"
	"prefilteredColor = texture(prefilterMap4, R).rgb;\n"
"}"
"else if(level >= 3)\n"
"{"
	"prefilteredColor = texture(prefilterMap3, R).rgb;\n"
"}"
"else if(level >= 2)\n"
"{"
	"prefilteredColor = texture(prefilterMap2, R).rgb;\n"
"}"
"else if(level >= 1)\n"
"{"
	"prefilteredColor = texture(prefilterMap1, R).rgb;\n"
"}"
"else if(level >= 0)\n"
"{"
	"prefilteredColor = texture(prefilterMap0, R).rgb;\n"
"}"
"vec2 brdf = texture(brdfLUT, vec2(max(dot(N, V), 0.0), roughness)).rg;									  \n"
"vec3 specular = prefilteredColor * (F * brdf.x + brdf.y);												  \n"
"vec3 ambient = (kD * diffuse + specular) * ao;															  \n"
"	vec3 color = ambient + Lo;																		\n"
"	color = color / (color + vec3(1.0));															\n"
"	color = pow(color, vec3(1.0 / 2.2));															\n"
"	FragColor = vec4(color, 1.0);																	\n"
//"	FragColor = vec4(1.0,0.0,0.0, 1.0);																	\n"
"}																									\n"

};

osg::ref_ptrosg::Geode CreateSphereGeode()
{
osg::ref_ptrosg::Geode geode = new osg::Geode;
osg::ref_ptrosg::Vec3Array vertices = new osg::Vec3Array(6);
(*vertices)[0].set(0.0f, 0.0f, 1.0f);
(*vertices)[1].set(-0.5f, -0.5f, 0.0f);
(*vertices)[2].set(0.5f, -0.5f, 0.0f);
(*vertices)[3].set(0.5f, 0.5f, 0.0f);
(*vertices)[4].set(-0.5f, 0.5f, 0.0f);
(*vertices)[5].set(0.0f, 0.0f, -1.0f);
osg::ref_ptrosg::DrawElementsUInt indices = new osg::DrawElementsUInt(GL_TRIANGLES, 24);
(*indices)[0] = 0; (*indices)[1] = 1; (*indices)[2] = 2;
(*indices)[3] = 0; (*indices)[4] = 2; (*indices)[5] = 3;
(*indices)[6] = 0; (*indices)[7] = 3; (*indices)[8] = 4;
(*indices)[9] = 0; (*indices)[10] = 4; (*indices)[11] = 1;
(*indices)[12] = 5; (*indices)[13] = 2; (*indices)[14] = 1;
(*indices)[15] = 5; (*indices)[16] = 3; (*indices)[17] = 2;
(*indices)[18] = 5; (*indices)[19] = 4; (*indices)[20] = 3;
(*indices)[21] = 5; (*indices)[22] = 1; (*indices)[23] = 4;
osg::ref_ptrosg::Geometry geom = new osg::Geometry;
geom->setVertexArray(vertices.get());
geom->addPrimitiveSet(indices.get());
osgUtil::SmoothingVisitor::smooth(*geom);
geode->addDrawable(geom);
return geode;

}

osg::ref_ptrosg::Geode renderSphere(osg::Vec3f pos)
{
osg::ref_ptrosg::Geode geode = new osg::Geode;
const unsigned int X_SEGMENTS = 64;
const unsigned int Y_SEGMENTS = 64;
const float PI = 3.14159265359f;
osg::ref_ptrosg::Vec3Array vertices = new osg::Vec3Array;
osg::ref_ptrosg::Vec3Array normalArray = new osg::Vec3Array;
for (unsigned int x = 0; x <= X_SEGMENTS; ++x)
{
for (unsigned int y = 0; y <= Y_SEGMENTS; ++y)
{
float xSegment = (float)x / (float)X_SEGMENTS;
float ySegment = (float)y / (float)Y_SEGMENTS;
float xPos = std::cos(xSegment * 2.0f * PI) * std::sin(ySegment * PI);
float yPos = std::cos(ySegment * PI);
float zPos = std::sin(xSegment * 2.0f * PI) * std::sin(ySegment * PI);

		vertices->push_back(osg::Vec3(xPos, yPos, zPos) + pos);
		normalArray->push_back(osg::Vec3(xPos, yPos, zPos));
	}
}
osg::ref_ptr indices = new osg::DrawElementsUInt();
bool oddRow = false;
for (unsigned int y = 0; y < Y_SEGMENTS; ++y)
{
	if (!oddRow) // even rows: y == 0, y == 2; and so on
	{
		for (unsigned int x = 0; x <= X_SEGMENTS; ++x)
		{
			indices->push_back(y       * (X_SEGMENTS + 1) + x);
			indices->push_back((y + 1) * (X_SEGMENTS + 1) + x);
		}
	}
	else
	{
		for (int x = X_SEGMENTS; x >= 0; --x)
		{
			indices->push_back((y + 1) * (X_SEGMENTS + 1) + x);
			indices->push_back(y       * (X_SEGMENTS + 1) + x);
		}
	}
	oddRow = !oddRow;
}
int indexCount = static_cast(indices->size());
indices->setMode(GL_TRIANGLE_STRIP);

osg::ref_ptr geom = new osg::Geometry;
geom->setVertexArray(vertices.get());
geom->addPrimitiveSet(indices.get());
geom->setNormalArray(normalArray, osg::Array::BIND_PER_VERTEX);

geom->setVertexAttribArray(1, vertices, osg::Array::BIND_PER_VERTEX);
geom->setVertexAttribArray(2, normalArray, osg::Array::BIND_PER_VERTEX);

//osgUtil::SmoothingVisitor::smooth(*geom);
geode->addDrawable(geom);
return geode;

}

class EyePointCallback : public osg::UniformCallback
{
public:
EyePointCallback(osg::ref_ptrosg::Camera camera)
{
_camera = camera;
}

virtual void operator() (osg::Uniform* uniform, osg::NodeVisitor* nv)
{
	osg::Vec3 eye, center, up;
	_camera->getViewMatrixAsLookAt(eye, center, up);
	uniform->set(eye);
}

private:
osg::ref_ptrosg::Camera _camera;
};

class ProjectMatrixCallback : public osg::UniformCallback
{
public:
ProjectMatrixCallback(osg::ref_ptrosg::Camera camera)
{
_camera = camera;
}

virtual void operator() (osg::Uniform* uniform, osg::NodeVisitor* nv)
{
	osg::Matrixd projectionMatrix = _camera->getProjectionMatrix();
	uniform->set(projectionMatrix);
}

private:
osg::ref_ptrosg::Camera _camera;
};
class ViewMatrixCallback : public osg::UniformCallback
{
public:
ViewMatrixCallback(osg::ref_ptrosg::Camera camera)
{
_camera = camera;
}

virtual void operator() (osg::Uniform* uniform, osg::NodeVisitor* nv)
{
	osg::Matrixd viewMatrix = _camera->getViewMatrix();
	uniform->set(viewMatrix);
}

private:
osg::ref_ptrosg::Camera _camera;
};
void setImagesByLevel(osg::ref_ptrosg::TextureCubeMap textureCubemap, int level)
{

textureCubemap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
textureCubemap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
textureCubemap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
textureCubemap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
textureCubemap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);

std::string strDir = "D:/hdr/Prefilter/" + std::to_string(level) + "/";
std::string strImagePosX = strDir + "Right face camera.bmp";
osg::ref_ptr imagePosX = osgDB::readImageFile(strImagePosX);
textureCubemap->setImage(osg::TextureCubeMap::POSITIVE_X, imagePosX);

std::string strImageNegX = strDir + "Left face camera.bmp";
osg::ref_ptr imageNegX = osgDB::readImageFile(strImageNegX);
textureCubemap->setImage(osg::TextureCubeMap::NEGATIVE_X, imageNegX);

std::string strImagePosY = strDir + "Front face camera.bmp";;
osg::ref_ptr imagePosY = osgDB::readImageFile(strImagePosY);
textureCubemap->setImage(osg::TextureCubeMap::POSITIVE_Y, imagePosY);
std::string strImageNegY = strDir + "Back face camera.bmp";;
osg::ref_ptr imageNegY = osgDB::readImageFile(strImageNegY);
textureCubemap->setImage(osg::TextureCubeMap::NEGATIVE_Y, imageNegY);

std::string strImagePosZ = strDir + "Top face camera.bmp";
osg::ref_ptr imagePosZ = osgDB::readImageFile(strImagePosZ);
textureCubemap->setImage(osg::TextureCubeMap::POSITIVE_Z, imagePosZ);
std::string strImageNegZ = strDir + "Bottom face camera.bmp";
osg::ref_ptr imageNegZ = osgDB::readImageFile(strImageNegZ);
textureCubemap->setImage(osg::TextureCubeMap::NEGATIVE_Z, imageNegZ);

}
int main()
{
//预过滤HDR环境贴图（第0-4层)

osg::ref_ptr prefilterMap_0 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_0, 0);
osg::ref_ptr prefilterMap_1 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_1, 1);
osg::ref_ptr prefilterMap_2 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_2, 2);
osg::ref_ptr prefilterMap_3 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_3, 3);
osg::ref_ptr prefilterMap_4 = new osg::TextureCubeMap;
setImagesByLevel(prefilterMap_4, 4);

//漫反射贴图
osg::ref_ptr irradianceTextureCubeMap = new osg::TextureCubeMap;
{
	irradianceTextureCubeMap->setTextureSize(512, 512);
	irradianceTextureCubeMap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
	irradianceTextureCubeMap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
	irradianceTextureCubeMap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
	irradianceTextureCubeMap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
	irradianceTextureCubeMap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);

	std::string strImagePosX = "D:/irradiance/Right face camera.bmp";
	osg::ref_ptr imagePosX = osgDB::readImageFile(strImagePosX);
	irradianceTextureCubeMap->setImage(osg::TextureCubeMap::POSITIVE_X, imagePosX);

	std::string strImageNegX = "D:/irradiance/Left face camera.bmp";
	osg::ref_ptr imageNegX = osgDB::readImageFile(strImageNegX);
	irradianceTextureCubeMap->setImage(osg::TextureCubeMap::NEGATIVE_X, imageNegX);

	std::string strImagePosY = "D:/irradiance/Front face camera.bmp";;
	osg::ref_ptr imagePosY = osgDB::readImageFile(strImagePosY);
	irradianceTextureCubeMap->setImage(osg::TextureCubeMap::POSITIVE_Y, imagePosY);
	std::string strImageNegY = "D:/irradiance/Back face camera.bmp";;
	osg::ref_ptr imageNegY = osgDB::readImageFile(strImageNegY);
	irradianceTextureCubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Y, imageNegY);

	std::string strImagePosZ = "D:/irradiance/Top face camera.bmp";
	osg::ref_ptr imagePosZ = osgDB::readImageFile(strImagePosZ);
	irradianceTextureCubeMap->setImage(osg::TextureCubeMap::POSITIVE_Z, imagePosZ);
	std::string strImageNegZ = "D:/irradiance/Bottom face camera.bmp";
	osg::ref_ptr imageNegZ = osgDB::readImageFile(strImageNegZ);
	irradianceTextureCubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Z, imageNegZ);
}
//积分贴图
osg::ref_ptr textureBRDFLUT = new osg::Texture2D;
{
	std::string strBRDFLUTImageName = "d:/hdr/lut/brdflut.bmp";
	osg::ref_ptr brdfLUTImage = osgDB::readImageFile(strBRDFLUTImageName);
	textureBRDFLUT->setImage(brdfLUTImage);
}


osg::ref_ptr prefilter0Uniform = new osg::Uniform("prefilterMap0", 0);
osg::ref_ptr prefilter1Uniform = new osg::Uniform("prefilterMap1",1);
osg::ref_ptr prefilter2Uniform = new osg::Uniform("prefilterMap2", 2);
osg::ref_ptr prefilter3Uniform = new osg::Uniform("prefilterMap3", 3);
osg::ref_ptr prefilter4Uniform = new osg::Uniform("prefilterMap4", 4);
osg::ref_ptr tex0Uniform = new osg::Uniform("irradianceMap", 5);
osg::ref_ptr brdfLUTUniform = new osg::Uniform("brdfLUT", 6);

osg::ref_ptr viewer = new osgViewer::Viewer;

osg::ref_ptr camera = viewer->getCamera();
osg::ref_ptr camPosUniform = new osg::Uniform("camPos", osg::Vec3f(0, 0, 0));
camPosUniform->setUpdateCallback(new EyePointCallback(camera));

osg::Matrix viewMatrix = camera->getViewMatrix();
osg::Matrix projMatrix = camera->getProjectionMatrix();
osg::Vec3f eye, center, up;
camera->getViewMatrixAsLookAt(eye, center, up);

//osg::ref_ptr camPosUniform = new osg::Uniform("camPos", eye);
osg::ref_ptr viewMatrixUniform = new osg::Uniform("view", viewMatrix);
viewMatrixUniform->setUpdateCallback(new ViewMatrixCallback(camera));
osg::ref_ptr projMatrixUniform = new osg::Uniform("projection", projMatrix);
projMatrixUniform->setUpdateCallback(new ProjectMatrixCallback(camera));
osg::ref_ptr grp = new osg::Group;
//漫反射比率
osg::Vec3f albedo(0.5f, 0.0f, 0.0f);
osg::ref_ptr albedoUniform = new osg::Uniform("albedo", albedo);
float ao = 1.0f;
osg::ref_ptr aoUniform = new osg::Uniform("ao", ao);

int nrRows = 7;
int nrColumns = 7;
float spacing = 2.5;
float ballRadius = 1.0f;

osg::ref_ptr lightColors = new osg::Vec3Array;
lightColors->push_back(osg::Vec3(300.0f, 300.0f, 300.0f));
lightColors->push_back(osg::Vec3(300.0f, 300.0f, 300.0f));
lightColors->push_back(osg::Vec3(300.0f, 300.0f, 300.0f));
lightColors->push_back(osg::Vec3(300.0f, 300.0f, 300.0f));

osg::ref_ptr lightColorsUniform = new osg::Uniform(osg::Uniform::FLOAT_VEC3, "lightColors", lightColors->size());
for (int i = 0; i < lightColors->size(); i++)
{
	lightColorsUniform->setElement(i, lightColors->at(i));
}
osg::ref_ptr lightPositions = new osg::Vec3Array;
lightPositions->push_back(osg::Vec3(-10.0f, 10.0f, 10.0f));
lightPositions->push_back(osg::Vec3(10.0f, 10.0f, 10.0f));
lightPositions->push_back(osg::Vec3(-10.0f, -10.0f, 10.0f));
lightPositions->push_back(osg::Vec3(10.0f, -10.0f, 10.0f));

osg::ref_ptr lightPositionsUniform = new osg::Uniform(osg::Uniform::FLOAT_VEC3, "lightPositions", lightPositions->size());
for (int i = 0; i < lightPositions->size(); i++)
{
	lightPositionsUniform->setElement(i, lightPositions->at(i));
}
for (int row = 0; row < nrRows; row++)
{
	float metallic = row * 1.0 / nrRows;
	for (int col = 0; col < nrColumns; col++)
	{
		float roughness = col * 1.0 / nrColumns;
		if (roughness <0.05)
		{
			roughness = 0.05;
		}
		if (roughness > 1.0)
		{
			roughness = 1.0;
		}
		osg::Vec3 ballCenter(
			(col - (nrColumns / 2)) * spacing,
			(row - (nrRows / 2)) * spacing,
			0.0f);
		osg::Matrix worldMatrix = osg::Matrix::translate(ballCenter);

		osg::Matrix inverse;
		inverse.invert(worldMatrix);
		osg::Matrix transPose;
		transPose.transpose(inverse);
		osg::ref_ptr geode = renderSphere(ballCenter);
		{
			osg::ref_ptr stateset = geode->getOrCreateStateSet();
			stateset->setTextureAttributeAndModes(0, prefilterMap_0, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(1, prefilterMap_1, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(2, prefilterMap_2, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(3, prefilterMap_3, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(4, prefilterMap_4, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(5, irradianceTextureCubeMap, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
			stateset->setTextureAttributeAndModes(6, textureBRDFLUT, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);



			osg::ref_ptr vs = new osg::Shader(osg::Shader::VERTEX, vertexShader_PBR);
			osg::ref_ptr ps = new osg::Shader(osg::Shader::FRAGMENT, psShader_PBR);
			osg::ref_ptr program = new osg::Program;
			program->addBindAttribLocation("aPos", 1);
			program->addBindAttribLocation("aNormal", 2);
			program->addShader(vs);
			program->addShader(ps);

			osg::ref_ptr metallicUniform = new osg::Uniform("metallic", metallic);
			osg::ref_ptr roughnessUniform = new osg::Uniform("roughness", roughness);
			//osg::ref_ptr transposeInverseMatrixUniform = new osg::Uniform("normalMatrix", transPose);

			osg::Uniform* transposeInverseMatrixUniform = stateset->getOrCreateUniform("normalMatrix", osg::Uniform::FLOAT_MAT4);
			transposeInverseMatrixUniform->set(transPose);
			stateset->addUniform(albedoUniform);
			stateset->addUniform(metallicUniform);
			stateset->addUniform(roughnessUniform);
			stateset->addUniform(aoUniform);
			stateset->addUniform(lightPositionsUniform);
			stateset->addUniform(lightColorsUniform);
			stateset->addUniform(transposeInverseMatrixUniform);
			stateset->addUniform(viewMatrixUniform);
			stateset->addUniform(projMatrixUniform);
			stateset->addUniform(camPosUniform);
			stateset->addUniform(tex0Uniform);
			stateset->addUniform(brdfLUTUniform);
			stateset->addUniform(prefilter0Uniform);
			stateset->addUniform(prefilter1Uniform);
			stateset->addUniform(prefilter2Uniform);
			stateset->addUniform(prefilter3Uniform);
			stateset->addUniform(prefilter4Uniform);
			stateset->setAttribute(program, osg::StateAttribute::ON);
		}
		grp->addChild(geode);
	}

}
grp->addChild(renderSphere(osg::Vec3(-10.0f, 10.0f, 10.0f)));
grp->addChild(renderSphere(osg::Vec3(10.0f, 10.0f, 10.0f)));
grp->addChild(renderSphere(osg::Vec3(-10.0f, -10.0f, 10.0f)));
grp->addChild(renderSphere(osg::Vec3(10.0f, -10.0f, 10.0f)));

viewer->getCamera()->setClearColor(osg::Vec4(0.1f, 0.1f, 0.1f, 1.0f));
viewer->setSceneData(grp);
viewer->run();

return 0;

}