Глава 27. Группы шейдеров

BK

Здесь я хочу добавить “reflection” (отражение) и “over mask” (трафарет) шейдеры, каждый из которых удвоит количество шейдер-программ. Соответственно, нужна функция, которая сможет загрузить группу шейдеров в 1 присест (например – Phong или flat для разных форматов данных). Также понадобится функция, которая выберет конкретный номер шейдера в зависимости от Материала (например – flat, ucolor, без текстур).

Вызов загрузки группы шейдеров будет выглядеть так:

loadShadersGroup("phong", "PHONG; COLOR | TEXTURE; NONE | OVERMASK", pFLvertex->pData, pFLfragment->pData);

Эта функция будет должна построить 4 шейдер-программы со следующими комбинациями defines:

  • PHONG + COLOR
  • PHONG + COLOR + OVERMASK
  • PHONG + TEXTURE
  • PHONG + TEXTURE + OVERMASK

Имплементация:

1. Запустим VS, откроем C:\CPP\a997modeler\p_windows\p_windows.sln.

Понадобятся новые функции и переменные в классе Shader.

2. Заменим Shader.h код на

#pragma once
#include "platform.h"
#include <string>
#include <vector>

class Shader
{
public:
    //Shader program's individual descriptor:
    unsigned int GLid = -1; // GL shader id
    char shaderType[20] = "";
    //common variables, "l_" for "location"
    //attributes
    int l_aPos; //attribute position (3D coordinates)
    int l_aTuv; //attribute TUV (texture coordinates)
    int l_aTuv2; //attribute TUV (texture coordinates for normal map)
    int l_aNormal; //attribute normal (3D vector)
    int l_aTangent; //for normal map
    int l_aBinormal; //for normal map
    //uniforms
    int l_uMVP; // transform matrix (Model-View-Projection)
    int l_uMV3x3; // Model-View matrix for normals
    int l_uVectorToLight; //required for light
    int l_uHalfVector; //required for specular light
    //material's properties
    int l_uColor;
    int l_uTex0; //texture id
    int l_uTex1mask; //transparency map
    int l_uTex2nm; //normal map
    int l_uTex3; //texture id
    int l_uTex1alphaChannelN; //alpha channel for mask
    int l_uTex1alphaNegative; //alpha channel negative
    int l_uTex0translateChannelN; //translate tex0 to tex3 by channelN.
    int l_uAlphaFactor; //for semi-transparency
    int l_uAlphaBlending; //for semi-transparency
    //light:
    int l_uAmbient; //ambient light
    //specular light parameters
    int l_uSpecularIntencity;
    int l_uSpecularMinDot;
    int l_uSpecularPowerOf;
    //end of descriptor

    //static array (vector) of all loaded shaders
    static std::vector<Shader*> shaders;

public:
    static int loadShaders();
    static int cleanUp();
    static unsigned int getGLid(int shN) { return shaders.at(shN)->GLid; };
    static int shaderErrorCheck(int shaderId, std::string ref);
    static int programErrorCheck(int programId, std::string ref);
    static int fillLocations(Shader* pSh);

    static int buildShaderObjectFromFiles(std::string filePathVertexS, std::string filePathFragmentS);
    static int linkShaderProgramFromFiles(const char* filePathVertexS, const char* filePathFragmentS);
	static int compileShaderFromFile(const char* filePath, GLenum shaderType);

    static int buildShaderObjectWithDefines(std::string shaderType, std::string definesString, char* sourceVertex, char* sourceFragment);
    static int linkShaderProgramWithDefines(std::string definesString, char* sourceVertex, char* sourceFragment);
    static int compileShaderWithDefines(std::string definesString, char* shaderSource, GLenum shaderType);

    static int loadShadersGroup(std::string shaderType, std::string optionsString, char* sourceVertex, char* sourceFragment);
};

3. Заменим Shader.cpp код на

#include "Shader.h"
#include "platform.h"
#include "utils.h"
#include "FileLoader.h"

extern std::string filesRoot;

//static array (vector) of all loaded shaders
std::vector<Shader*> Shader::shaders;

int Shader::loadShaders() {
    FileLoader* pFLvertex = new FileLoader("/dt/shaders/phong_v.txt");
    FileLoader* pFLfragment = new FileLoader("/dt/shaders/phong_f.txt");
    loadShadersGroup("flat", "FLAT; COLOR | TEXTURE; NONE | OVERMASK", pFLvertex->pData, pFLfragment->pData);
    loadShadersGroup("phong", "PHONG; COLOR | TEXTURE; NONE | OVERMASK", pFLvertex->pData, pFLfragment->pData);
    loadShadersGroup("mirror", "PHONG;MIRROR; NONE | OVERMASK", pFLvertex->pData, pFLfragment->pData);
    delete pFLvertex;
    delete pFLfragment;
    return 1;
}
int Shader::buildShaderObjectFromFiles(std::string filePathVertexS, std::string filePathFragmentS) {
    //create shader object
    Shader* pSh = new Shader();
    shaders.push_back(pSh);
    pSh->GLid = linkShaderProgramFromFiles((filesRoot + filePathVertexS).c_str(), (filesRoot + filePathFragmentS).c_str());
    //common variables. If not presented, = -1;
    fillLocations(pSh);

    return (shaders.size() - 1);
}
int Shader::fillLocations(Shader* pSh) {
    //common variables. If not presented, = -1;
    //attributes
    pSh->l_aPos = glGetAttribLocation(pSh->GLid, "aPos"); //attribute position (3D coordinates)
    pSh->l_aNormal = glGetAttribLocation(pSh->GLid, "aNormal"); //attribute normal (3D vector)
    pSh->l_aTangent = glGetAttribLocation(pSh->GLid, "aTangent"); //for normal map
    pSh->l_aBinormal = glGetAttribLocation(pSh->GLid, "aBinormal"); //for normal map
    pSh->l_aTuv = glGetAttribLocation(pSh->GLid, "aTuv"); //attribute TUV (texture coordinates)
    pSh->l_aTuv2 = glGetAttribLocation(pSh->GLid, "aTuv2"); //attribute TUV (texture coordinates)
    //uniforms
    pSh->l_uMVP = glGetUniformLocation(pSh->GLid, "uMVP"); // transform matrix (Model-View-Projection)
    pSh->l_uMV3x3 = glGetUniformLocation(pSh->GLid, "uMV3x3"); // Model-View matrix for normals
    pSh->l_uVectorToLight = glGetUniformLocation(pSh->GLid, "uVectorToLight"); // 
    pSh->l_uHalfVector = glGetUniformLocation(pSh->GLid, "uHalfVector"); // required for specular light
    //material's properties
    pSh->l_uColor = glGetUniformLocation(pSh->GLid, "uColor");
    pSh->l_uTex0 = glGetUniformLocation(pSh->GLid, "uTex0"); //texture id
    pSh->l_uTex1mask = glGetUniformLocation(pSh->GLid, "uTex1mask"); //texture id
    pSh->l_uTex2nm = glGetUniformLocation(pSh->GLid, "uTex2nm"); //texture id
    pSh->l_uTex3 = glGetUniformLocation(pSh->GLid, "uTex3"); //texture id
    pSh->l_uTex1alphaChannelN = glGetUniformLocation(pSh->GLid, "uTex1alphaChannelN");
    pSh->l_uTex1alphaNegative = glGetUniformLocation(pSh->GLid, "uTex1alphaNegative");
    pSh->l_uTex0translateChannelN = glGetUniformLocation(pSh->GLid, "uTex0translateChannelN");
    pSh->l_uAlphaFactor = glGetUniformLocation(pSh->GLid, "uAlphaFactor"); // for semi-transparency
    pSh->l_uAlphaBlending = glGetUniformLocation(pSh->GLid, "uAlphaBlending"); // for semi-transparency
    pSh->l_uAmbient = glGetUniformLocation(pSh->GLid, "uAmbient"); // ambient light
    pSh->l_uSpecularIntencity = glGetUniformLocation(pSh->GLid, "uSpecularIntencity"); // 
    pSh->l_uSpecularMinDot = glGetUniformLocation(pSh->GLid, "uSpecularMinDot"); // 
    pSh->l_uSpecularPowerOf = glGetUniformLocation(pSh->GLid, "uSpecularPowerOf"); // 
    return 1;
}
int Shader::cleanUp() {
    int shadersN = shaders.size();
    if (shadersN < 1)
        return -1;
    glUseProgram(0);
    for (int i = 0; i < shadersN; i++) {
        Shader* pSh = shaders.at(i);
        glDeleteProgram(pSh->GLid);
        delete pSh;
    }
    shaders.clear();
    return 1;
}

GLchar infoLog[1024];
int logLength;
int Shader::shaderErrorCheck(int shaderId, std::string ref) {
    //use after glCompileShader()
    if (checkGLerrors(ref) > 0)
        return -1;
    glGetShaderInfoLog(shaderId, 1024, &logLength, infoLog);
    if (logLength == 0)
        return 0;
    mylog("%s shader infoLog:\n%s\n", ref.c_str(), infoLog);
    return -1;
}
int Shader::programErrorCheck(int programId, std::string ref) {
    //use after glLinkProgram()
    if (checkGLerrors(ref) > 0)
        return -1;
    glGetProgramInfoLog(programId, 1024, &logLength, infoLog);
    if (logLength == 0)
        return 0;
    mylog("%s program infoLog:\n%s\n", ref.c_str(), infoLog);
    return -1;
}

int Shader::compileShaderFromFile(const char* filePath, GLenum shaderType) {
    int shaderId = glCreateShader(shaderType);
    FILE* pFile;
    myFopen_s(&pFile, filePath, "rt");
    if (pFile != NULL)
    {
        // obtain file size:
        fseek(pFile, 0, SEEK_END);
        int fSize = ftell(pFile);
        rewind(pFile);
        // size obtained, create buffer
        char* shaderSource = new char[fSize + 1];
        fSize = fread(shaderSource, 1, fSize, pFile);
        shaderSource[fSize] = 0;
        fclose(pFile);
        // source code loaded, compile
        glShaderSource(shaderId, 1, (const GLchar**)&shaderSource, NULL);
        //myglErrorCheck("glShaderSource");
        glCompileShader(shaderId);
        if (shaderErrorCheck(shaderId, "glCompileShader") < 0)
            return -1;
        delete[] shaderSource;
    }
    else {
        mylog("ERROR loading %s\n", filePath);
        return -1;
    }
    return shaderId;
}
int Shader::linkShaderProgramFromFiles(const char* filePathVertexS, const char* filePathFragmentS) {
    int vertexShaderId = compileShaderFromFile(filePathVertexS, GL_VERTEX_SHADER);
    int fragmentShaderId = compileShaderFromFile(filePathFragmentS, GL_FRAGMENT_SHADER);
    int programId = glCreateProgram();
    glAttachShader(programId, vertexShaderId);
    glAttachShader(programId, fragmentShaderId);
    glLinkProgram(programId);
    if (programErrorCheck(programId, "glLinkProgram") < 0)
        return -1;
    //don't need shaders any longer - detach and delete them
    glDetachShader(programId, vertexShaderId);
    glDetachShader(programId, fragmentShaderId);
    glDeleteShader(vertexShaderId);
    glDeleteShader(fragmentShaderId);
    return programId;
}

int Shader::buildShaderObjectWithDefines(std::string shaderType, std::string definesString, char* sourceVertex, char* sourceFragment) {
    //create shader object
    Shader* pSh = new Shader();
    shaders.push_back(pSh);
    myStrcpy_s(pSh->shaderType, 20, shaderType.c_str());

    pSh->GLid = linkShaderProgramWithDefines(definesString, sourceVertex, sourceFragment);
    //common variables. If not presented, = -1;
    fillLocations(pSh);

    return (shaders.size() - 1);
}
int Shader::linkShaderProgramWithDefines(std::string definesString00, char* sourceVertex, char* sourceFragment) {
    //build extended definesString
    bool bUSE_NORMALS = false;
    bool bUSE_TEX0 = false;
    bool bUSE_TUV0 = false;
    if (definesString00.find(" PHONG\n") != std::string::npos)
        bUSE_NORMALS = true;
    if (definesString00.find(" TEXTURE\n") != std::string::npos) {
        bUSE_TEX0 = true;
        bUSE_TUV0 = true;
    }
    if (definesString00.find(" MIRROR\n") != std::string::npos) {
        bUSE_NORMALS = true;
        bUSE_TEX0 = true;
    }
    if (definesString00.find(" OVERMASK\n") != std::string::npos) {
        bUSE_TUV0 = true;
    }
    std::string definesString;
    definesString.assign("#version 320 es\n");
    definesString.append(definesString00);
    if (bUSE_NORMALS)
        definesString.append("#define USE_NORMALS\n");
    if (bUSE_TEX0)
        definesString.append("#define USE_TEX0\n");
    if (bUSE_TUV0)
        definesString.append("#define USE_TUV0\n");

    int vertexShaderId = compileShaderWithDefines(definesString, sourceVertex, GL_VERTEX_SHADER);
    int fragmentShaderId = compileShaderWithDefines(definesString, sourceFragment, GL_FRAGMENT_SHADER);

    int programId = glCreateProgram();
    glAttachShader(programId, vertexShaderId);
    glAttachShader(programId, fragmentShaderId);
    glLinkProgram(programId);
    if (programErrorCheck(programId, "glLinkProgram") < 0)
        return -1;
    //don't need shaders any longer - detach and delete them
    glDetachShader(programId, vertexShaderId);
    glDetachShader(programId, fragmentShaderId);
    glDeleteShader(vertexShaderId);
    glDeleteShader(fragmentShaderId);
    //mylog("linking program\n%s\n", definesString.c_str());
    return programId;
}
int Shader::compileShaderWithDefines(std::string definesString, char* shaderSource, GLenum shaderType) {
    int shaderId = glCreateShader(shaderType);
    if (definesString.empty())
        glShaderSource(shaderId, 1, (const GLchar**)&shaderSource, NULL);
    else { //2 strings
        const char* sourceStrings[2];
        sourceStrings[0] = definesString.c_str();
        sourceStrings[1] = shaderSource;
        // source code loaded, compile
        glShaderSource(shaderId, 2, (const GLchar**)sourceStrings, NULL);
    }
    //myglErrorCheck("glShaderSource");
    glCompileShader(shaderId);
    if (shaderErrorCheck(shaderId, "glCompileShader") < 0) {
        mylog("ERROR in compileShader,\n%s\n%s\n", definesString.c_str(), shaderSource);
        return -1;
    }
    return shaderId;
}

int Shader::loadShadersGroup(std::string shaderType, std::string optionsString, char* sourceVertex, char* sourceFragment) {
    struct Terms {
        std::vector<std::string> terms;
        int totalN = 0;
        int currentN = 0;
    };
    std::vector<Terms*> terms;
    std::vector<std::string> termGroups = splitString(optionsString, ";");
    int groupsN = termGroups.size();
    for (int groupN = 0; groupN < groupsN; groupN++) {
        Terms* pTerms = new Terms();
        terms.push_back(pTerms);
        pTerms->terms = splitString(termGroups.at(groupN), "|");
        pTerms->totalN = pTerms->terms.size();
    }
    while (1) {
        std::string definesString = "";
        for (int groupN = 0; groupN < groupsN; groupN++) {
            Terms* pTerms = terms.at(groupN);
            std::string term = pTerms->terms.at(pTerms->currentN);
            if (term.compare("NONE") != 0) {
                definesString.append("#define ");
                definesString.append(term);
                definesString.append("\n");
            }
        }
        int shaderObjN = buildShaderObjectWithDefines(shaderType, definesString, sourceVertex, sourceFragment);
        //go to next terms combo
        bool noMoreOptions = false;
        for (int groupN = groupsN - 1; groupN >= 0; groupN--) {
            Terms* pTerms = terms.at(groupN);
            if (pTerms->currentN < pTerms->totalN - 1) {
                pTerms->currentN++;
                break;
            }
            else { // the level exhausted
                pTerms->currentN = 0;
                //proceed to upper level
                if (groupN == 0) {
                    noMoreOptions = true;
                    break;
                }
            }
        }
        if (noMoreOptions)
            break;
    }
    return 1;
}

  • Заметьте: всего 3 вызова генерируют ДЕСЯТЬ шейдер-программ из всего ОДНОЙ пары шейдеров.

Теперь – сами шейдеры.

4. Vertex shader:

//#version 320 es
precision lowp float;
uniform mat4 uMVP; // transform matrix (Model-View-Projection)
uniform mat3 uMV3x3; // Model-View matrix (for calculating normals into eye space)

in vec3 aPos; // position attribute (x,y,z)
#if defined(USE_NORMALS)
	in vec3 aNormal; // normal attribute (x,y,z)
	out vec3 vNormal; // varying normal (to pass to fragment shader)
#endif
#if defined(USE_TUV0)
	in vec2 aTuv; //attribute TUV (texture coordinates)
	out vec2 vTuv; //varying TUV (pass to fragment shader)
#endif
#if defined(MIRROR)
	out vec2 vTuvMirror; //varying TUV (pass to fragment shader)
#endif

void main(void) { 
	gl_Position = uMVP * vec4(aPos, 1.0);
#if defined(USE_NORMALS)	
	// Transform the normal's orientation into eye space. 
	vNormal = uMV3x3 * aNormal;	
#endif
#if defined(USE_TUV0)
	vTuv = aTuv;
#endif
#if defined(MIRROR)
	vTuvMirror[0] =  (gl_Position[0]/gl_Position[3]*0.1+vNormal[0]*0.4)+0.5;
	vTuvMirror[1] = -(gl_Position[1]/gl_Position[3]*0.1+vNormal[1]*0.4)+0.5;
#endif
}

Копируем этот код в Текстовый редактор и сохраняем как (overwrite)

C:\CPP\engine\dt\shaders\phong_v.txt

  • На всякий случай: reflection (отражение, строки с 28 по 31): мы берем картинку белого шума (из прошлой главы) в качестве текстуры, потом вычисляем текстурные tUV координаты из экранной позиции вертекса и направления нормали. Конструкция “gl_Position[0]/gl_Position[3]” дает нам кординаты в GLформате (от -1 до 1) . Конструкция в скобках дает комбинацию позиции + направление в диапазоне от -0.5 до 0.5. Таким образом, vTuvMirror – это преобразование позиции/ориентации в текстурные tUV координаты.

5. Fragment shader:

//#version 320 es
precision lowp float;
out vec4 FragColor; //output pixel color
uniform float uAlphaFactor; //for semi-transparency
uniform int uAlphaBlending; //for semi-transparency

#if defined(USE_NORMALS)
	in vec3 vNormal; //normal passed from rasterizer
#endif
#if defined(USE_TEX0)
	uniform sampler2D uTex0;  //texture id
	uniform sampler2D uTex3;  //translate texture id
	uniform int uTex0translateChannelN;
#else
	uniform vec4 uColor;
#endif
#if defined(USE_TUV0)
	in vec2 vTuv; //varying TUV (passed from vertex shader)
#endif
#if defined(MIRROR)
	in vec2 vTuvMirror; //varying TUV (passed from vertex shader)
#endif
#if defined(OVERMASK)
	uniform sampler2D uTex1mask;  //texture id
	uniform int uTex1alphaChannelN;
	uniform int uTex1alphaNegative;
#endif

#if defined(PHONG)
	uniform float uAmbient;
	uniform float uSpecularIntencity;
	uniform float uSpecularMinDot;
	uniform float uSpecularPowerOf;

	uniform vec3 uVectorToLight;
	uniform vec3 uHalfVector;
#endif

void main(void) {

	vec4 outColor;
	float alpha = 1.0;
#if defined(OVERMASK)
	outColor = texture(uTex1mask, vTuv);
	alpha = outColor[uTex1alphaChannelN];
	if(uTex1alphaNegative > 0)
		alpha = 1.0 - alpha;
	if(alpha < 0.5){
		if(uAlphaBlending > 0){
			if(alpha == 0.0){
				discard;
				return;
			}
		}
		else{ //no AlphaBlending
			discard;
			return;
		}
	}
#endif
#if defined(USE_TEX0)
	#if defined(MIRROR)
		outColor = texture(uTex0, vTuvMirror);
	#else
		outColor = texture(uTex0, vTuv);
	#endif
	if(uTex0translateChannelN >= 0){ //translate channel
		vec2 tuv3;
		tuv3[0] = outColor[uTex0translateChannelN];
		tuv3[1] = 0.0;
		outColor = texture(uTex3, tuv3);
	}
	FragColor = outColor;
#else
	FragColor = uColor;
#endif
	if(FragColor.a != 1.0){
		alpha *= FragColor.a;
		if(alpha < 0.5){
			if(uAlphaBlending > 0){
				if(alpha == 0.0){
					discard;
					return;
				}
			}
			else{ //no AlphaBlending
				discard;
				return;
			}
		}
	}

#if defined(USE_NORMALS)
	vec3 vNormalNormal = normalize(vNormal);
#endif

#if defined(PHONG)
	if(uAmbient<1.0){
		 // Calculate the dot product of the light vector and vertex normal. If the normal and light vector are
		 // pointing in the same direction then it will get max illumination.
		 float directionalLightIntencity = dot(vNormalNormal, uVectorToLight);
		
		 // count ambient component
		 directionalLightIntencity += uAmbient;
		 if(directionalLightIntencity < uAmbient)
			directionalLightIntencity = uAmbient;

		 // Multiply the color by the lightIntencity illumination level to get final output color.
		 FragColor *= directionalLightIntencity;
	}
	if(uSpecularIntencity>0.0){
		//specular light
		// INTENSITY OF THE SPECULAR LIGHT
		// DOT PRODUCT OF NORMAL VECTOR AND THE HALF VECTOR TO THE POWER OF THE SPECULAR HARDNESS
		float dotProduct = dot(vNormalNormal, uHalfVector);

		if(dotProduct>uSpecularMinDot){
			float specularIntencity = pow(dotProduct, uSpecularPowerOf) * uSpecularIntencity;		
			if(specularIntencity > uSpecularIntencity)
				specularIntencity = uSpecularIntencity;
			FragColor += specularIntencity;
		}
	}
#endif
	if(uAlphaFactor != 1.0)
		alpha *= uAlphaFactor;	
	FragColor.a = alpha;
}

Копируем этот код в Текстовый редактор и сохраняем как (overwrite)

C:\CPP\engine\dt\shaders\phong_f.txt

Пояснения:

  • Строка 45. Для карты прозрачности (трафарета) номер канала uTex1alphaChannelN по умолчанию 3 (Alpha-channel), но может быть любым из 4-х RGBA каналов.
  • Строки 67-72. Если uTex0translateChannelN задан (>=0), тогда мы преобразуем его черно-белое значение в цвета, заданные в 1-мерной uTex3 текстуре.

По поводу “преобразования” в 1-мерную текстуру:

Например, золото. У нас это будет 4х1 текстура:

6. В Windows File Explorer-е создадим новый под-каталог C:\CPP\engine\dt\common\img\materials

Затем сгрузим gold01.bmp здесь

и сохраним его в/как C:\CPP\engine\dt\common\img\materials\gold01.bmp

В классе Material – новые функции и переменная shaderType

7. Заменим Material.h код на:

#pragma once
#include "MyColor.h"
#include <string>

class Material
{
public:
	char shaderType[20] = "";
	int shaderN = -1;
	int primitiveType = GL_TRIANGLES;
	MyColor uColor;
	int uTex0 = -1;
	int uTex1mask = -1;
	int uTex2nm = -1;
	int uTex3 = -1;
	int uTex1alphaChannelN = 3; //default - alpha channel for mask
	int uTex1alphaNegative = 0; //default - alpha channel not negative
	int uTex0translateChannelN = -1; //translate tex0 to tex3 by channelN. Default -1 - don't translate

	int uAlphaBlending = 0; //for semi-transparency
	float uAlphaFactor = 1; //for semi-transparency
	float uAmbient = 0.4f; //ambient light
	//specular light parameters
	float uSpecularIntencity = 0.8f;
	float uSpecularMinDot = 0.95f;
	float uSpecularPowerOf = 20.0f;

public:
	int pickShaderNumber() { return pickShaderNumber(this); };
	static int pickShaderNumber(Material* pMT);
	void setShaderType(std::string needType) { setShaderType(this, needType); };
	static void setShaderType(Material* pMT, std::string needType) { myStrcpy_s(pMT->shaderType, 20, (char*)needType.c_str()); };
	void clear() { clear(this); };
	static void clear(Material* pMT);
	int assignShader(std::string needType) { return assignShader(this, needType); };
	static int assignShader(Material* pMT, std::string needType);
};

8. Заменим наш все еще пустой Material.cpp на: 

#include "Material.h"
#include "Shader.h"
#include "platform.h"

int Material::pickShaderNumber(Material* pMT) {
    int shadersN = Shader::shaders.size();
    for (int i = 0; i < shadersN; i++) {
        Shader* pSH = Shader::shaders.at(i);
        if (strcmp(pMT->shaderType, pSH->shaderType) != 0)
            continue;
        if (pMT->uColor.isZero() != (pSH->l_uColor < 0))
            continue;
        if ((pMT->uTex0 < 0) != (pSH->l_uTex0 < 0))
            continue;
        if ((pMT->uTex1mask < 0) != (pSH->l_uTex1mask < 0))
            continue;
        if ((pMT->uTex2nm < 0) != (pSH->l_uTex2nm < 0))
            continue;
        pMT->shaderN = i;
        return i;
    }
    mylog("ERROR in Material::pickShaderNumber:\n");
    mylog("Can't find '%s' shader for uColor=%08x uTex0=%d uTex1mask=%d uTex2nm=%d\n",
        pMT->shaderType, pMT->uColor.getUint32(), pMT->uTex0, pMT->uTex1mask, pMT->uTex2nm);
    return -1;
}

void Material::clear(Material* pMT) {
    Material mtZero;
    memcpy(pMT, &mtZero, sizeof(Material));
}
int Material::assignShader(Material* pMT, std::string shaderType) {
    setShaderType(pMT, shaderType);
    return pickShaderNumber(pMT);
}

Теперь ModelBuilder1base, когда строит DrawJobs, подбирает номер шейдера программно (строка 228).

9. Заменим ModelBuilder1base.cpp код на

#include "ModelBuilder1base.h"
#include "platform.h"
#include "utils.h"
#include "DrawJob.h"
#include "Shader.h"

extern float degrees2radians;

ModelBuilder1base::~ModelBuilder1base() {
	//clear all vectors
	int itemsN = vertices.size();
	for (int i = 0; i < itemsN; i++)
		delete vertices.at(i);
	vertices.clear();

	itemsN = triangles.size();
	for (int i = 0; i < itemsN; i++)
		delete triangles.at(i);
	triangles.clear();

	itemsN = vShapesStack.size();
	for (int i = 0; i < itemsN; i++)
		delete vShapesStack.at(i);
	vShapesStack.clear();

	itemsN = groupsStack.size();
	for (int i = 0; i < itemsN; i++)
		delete groupsStack.at(i);
	groupsStack.clear();

	itemsN = materialsList.size();
	for (int i = 0; i < itemsN; i++)
		delete materialsList.at(i);
	materialsList.clear();

	subjNumbersList.clear();
}
int ModelBuilder1base::useSubjN(ModelBuilder1base* pMB, int subjN) {
	pMB->usingSubjN = subjN;
	int itemsN = pMB->subjNumbersList.size();
	bool newN = true;
	if (itemsN > 0)
		for (int i = 0; i < itemsN; i++)
			if (pMB->subjNumbersList.at(i) == subjN) {
				newN = false;
				break;
			}
	if (newN)
		pMB->subjNumbersList.push_back(subjN);
	return subjN;
}
int ModelBuilder1base::useMaterial(ModelBuilder1base* pMB, Material* pMT) {
	int itemsN = pMB->materialsList.size();
	if (itemsN > 0)
		for (int i = 0; i < itemsN; i++)
			if (memcmp(pMB->materialsList.at(i), pMT, sizeof(Material)) == 0) {
				pMB->usingMaterialN = i;
				return i;
			}
	//if here - add new material to the list
	pMB->usingMaterialN = itemsN;
	//create a copy of new Material and add to the list
	Material* pMTnew = new Material(*pMT);
	pMB->materialsList.push_back(pMTnew);
	return itemsN;
}
int ModelBuilder1base::add2triangles(ModelBuilder1base* pMB, int nNW, int nNE, int nSW, int nSE, int n) {
	//indexes: NorthWest, NorthEast, SouthWest,SouthEast
	if (n % 2 == 0) { //even number
		addTriangle(pMB, nNW, nSW, nNE);
		addTriangle(pMB, nNE, nSW, nSE);
	}
	else { //odd number
		addTriangle(pMB, nNW, nSE, nNE);
		addTriangle(pMB, nNW, nSW, nSE);
	}
	return pMB->triangles.size() - 1;
}
int ModelBuilder1base::addTriangle(ModelBuilder1base* pMB, int i0, int i1, int i2) {
	Triangle01* pTR = new Triangle01();
	pMB->triangles.push_back(pTR);
	pTR->idx[0] = i0;
	pTR->idx[1] = i1;
	pTR->idx[2] = i2;
	pTR->subjN = pMB->usingSubjN;
	pTR->materialN = pMB->usingMaterialN;
	return pMB->triangles.size() - 1;
}
void ModelBuilder1base::lockGroup(ModelBuilder1base* pMB) {
	if (pMB->pCurrentGroup != NULL)
		pMB->groupsStack.push_back(pMB->pCurrentGroup);
	pMB->pCurrentGroup = new Group01();
	pMB->pCurrentGroup->fromVertexN = pMB->vertices.size();
	pMB->pCurrentGroup->fromTriangleN = pMB->triangles.size();
}
void ModelBuilder1base::releaseGroup(ModelBuilder1base* pMB) {
	delete pMB->pCurrentGroup;
	if (pMB->groupsStack.size() > 0) {
		pMB->pCurrentGroup = pMB->groupsStack.back();
		pMB->groupsStack.pop_back();
	}
	else
		pMB->pCurrentGroup = NULL;
}
int ModelBuilder1base::addVertex(ModelBuilder1base* pMB, float kx, float ky, float kz, float nx, float ny, float nz) {
	Vertex01* pVX = new Vertex01();
	pMB->vertices.push_back(pVX);
	pVX->aPos[0] = kx;
	pVX->aPos[1] = ky;
	pVX->aPos[2] = kz;
	//normal
	pVX->aNormal[0] = nx;
	pVX->aNormal[1] = ny;
	pVX->aNormal[2] = nz;
	pVX->subjN = pMB->usingSubjN;
	pVX->materialN = pMB->usingMaterialN;
	return pMB->vertices.size() - 1;
}
int ModelBuilder1base::buildDrawJobs(ModelBuilder1base* pMB, std::vector<GameSubj*> gameSubjs) {
	int totalSubjsN = pMB->subjNumbersList.size();
	if (totalSubjsN < 1) {
		pMB->subjNumbersList.push_back(-1);
		totalSubjsN = 1;
	}
	int totalMaterialsN = pMB->materialsList.size();
	if (totalSubjsN < 2 && totalMaterialsN < 2) {
		//simple single DrawJob
		Material* pMT = pMB->materialsList.at(0);
		GameSubj* pGS = NULL;
		int gsN = pMB->subjNumbersList.at(0);
		if (gsN >= 0)
			pGS = gameSubjs.at(gsN);
		if (pGS != NULL)
			pGS->djStartN = DrawJob::drawJobs.size();
		buildSingleDrawJob(pMT, pMB->vertices, pMB->triangles);
		if (pGS != NULL)
			pGS->djTotalN = DrawJob::drawJobs.size() - pGS->djStartN;
		return 1;
	}
	int totalVertsN = pMB->vertices.size();
	int totalTrianglesN = pMB->triangles.size();
	//clear flags
	for (int vN = 0; vN < totalVertsN; vN++) {
		Vertex01* pVX = pMB->vertices.at(vN);
		pVX->flag = 0;
	}
	for (int tN = 0; tN < totalTrianglesN; tN++) {
		Triangle01* pTR = pMB->triangles.at(tN);
		pTR->flag = 0;
	}
	int addedDJs = 0;
	for (int sN = 0; sN < totalSubjsN; sN++) {
		GameSubj* pGS = NULL;
		int gsN = pMB->subjNumbersList.at(sN);
		if (gsN >= 0)
			pGS = gameSubjs.at(gsN);
		if (pGS != NULL)
			pGS->djStartN = DrawJob::drawJobs.size();
		for (int mtN = 0; mtN < totalMaterialsN; mtN++) {
			Material* pMT = pMB->materialsList.at(mtN);
			std::vector<Vertex01*> useVertices;
			std::vector<Triangle01*> useTriangles;
			for (int vN = 0; vN < totalVertsN; vN++) {
				Vertex01* pVX = pMB->vertices.at(vN);
				if (pVX->flag != 0)
					continue;
				if (pVX->subjN != gsN)
					continue;
				if (pVX->materialN != mtN)
					continue;
				//if here - make a copy
				Vertex01* pVX2 = new Vertex01(*pVX);
				useVertices.push_back(pVX2);
				pVX2->altN = vN;
				pVX->flag = 1;
				if (pVX->endOfSequence > 0) {
					rearrangeArraysForDrawJob(pMB, pMB->vertices, useVertices, useTriangles);
					buildSingleDrawJob(pMT, useVertices, useTriangles);
					addedDJs++;
					//clear and proceed to next sequence
					int useVerticesN = useVertices.size();
					for (int i = 0; i < useVerticesN; i++)
						delete useVertices.at(i);
					useVertices.clear();
				}
			}
			int useVerticesN = useVertices.size();
			if (useVerticesN < 1)
				continue; //to next material
			//pick triangles
			for (int tN = 0; tN < totalTrianglesN; tN++) {
				Triangle01* pTR = pMB->triangles.at(tN);
				if (pTR->flag != 0)
					continue;
				if (pTR->subjN != gsN)
					continue;
				if (pTR->materialN != mtN)
					continue;
				//if here - make a copy
				Triangle01* pTR2 = new Triangle01(*pTR);
				useTriangles.push_back(pTR2);
				pTR->flag = 1;
			}
			rearrangeArraysForDrawJob(pMB, pMB->vertices, useVertices, useTriangles);
			buildSingleDrawJob(pMT, useVertices, useTriangles);
			addedDJs++;
			//clear all for next material
			for (int i = 0; i < useVerticesN; i++)
				delete useVertices.at(i);
			useVertices.clear();
			int useTrianglesN = useTriangles.size();
			for (int i = 0; i < useTrianglesN; i++)
				delete useTriangles.at(i);
			useTriangles.clear();
		}
		if (pGS != NULL)
			pGS->djTotalN = DrawJob::drawJobs.size() - pGS->djStartN;
	}
	return addedDJs;
}

int ModelBuilder1base::buildSingleDrawJob(Material* pMT, std::vector<Vertex01*> useVertices, std::vector<Triangle01*> useTriangles) {
	int totalVertsN = useVertices.size();
	if (totalVertsN < 1)
		return 0;
	//if (pMT->uTex2nm >= 0)
	//	calculateTangentSpace(useVertices, useTriangles);
	pMT->pickShaderNumber();
	DrawJob* pDJ = new DrawJob();
	//copy material to DJ
	memcpy(&pDJ->mt, pMT, sizeof(Material));
	//calculate VBO element size (stride) and variables offsets in VBO
	int VBOid = DrawJob::newBufferId();
	int stride = 0;
	pDJ->setDesirableOffsets(&stride, pDJ->mt.shaderN, VBOid);
	//create an array for VBO
	int bufferSize = totalVertsN * stride;
	float* vertsBuffer = new float[bufferSize];
	//fill vertsBuffer
	Shader* pSh = Shader::shaders.at(pDJ->mt.shaderN);
	int floatSize = sizeof(float);
	for (int vN = 0; vN < totalVertsN; vN++) {
		Vertex01* pVX = useVertices.at(vN);
		int idx = vN * stride / floatSize;
		//pick data from vertex and move to the buffer
		memcpy(&vertsBuffer[idx + pDJ->aPos.offset / floatSize], pVX->aPos, 3 * floatSize);
		if (pSh->l_aNormal >= 0) //normal
			memcpy(&vertsBuffer[idx + pDJ->aNormal.offset / floatSize], pVX->aNormal, 3 * floatSize);
		if (pSh->l_aTuv >= 0) //attribute TUV (texture coordinates)
			memcpy(&vertsBuffer[idx + pDJ->aTuv.offset / floatSize], pVX->aTuv, 2 * floatSize);
		if (pSh->l_aTuv2 >= 0) //attribute TUV2 (normal maps)
			memcpy(&vertsBuffer[idx + pDJ->aTuv2.offset / floatSize], pVX->aTuv2, 2 * floatSize);
		if (pSh->l_aTangent >= 0)
			memcpy(&vertsBuffer[idx + pDJ->aTangent.offset / floatSize], pVX->aTangent, 3 * floatSize);
		if (pSh->l_aBinormal >= 0)
			memcpy(&vertsBuffer[idx + pDJ->aBinormal.offset / floatSize], pVX->aBinormal, 3 * floatSize);
	}
	//buffer is ready, create VBO
	glBindBuffer(GL_ARRAY_BUFFER, VBOid);
	glBufferData(GL_ARRAY_BUFFER, bufferSize * floatSize, vertsBuffer, GL_STATIC_DRAW);
	delete[] vertsBuffer;
	pDJ->pointsN = totalVertsN;

	int totalTrianglesN = useTriangles.size();
	if (totalTrianglesN > 0) {
		//create EBO
		int totalIndexesN = totalTrianglesN * 3;
		//create buffer
		GLushort* indexBuffer = new GLushort[totalIndexesN];
		for (int tN = 0; tN < totalTrianglesN; tN++) {
			Triangle01* pTR = useTriangles[tN];
			int idx = tN * 3;
			indexBuffer[idx] = (GLushort)pTR->idx[0];
			indexBuffer[idx + 1] = (GLushort)pTR->idx[1];
			indexBuffer[idx + 2] = (GLushort)pTR->idx[2];
		}
		//buffer is ready, create IBO
		pDJ->glEBOid = DrawJob::newBufferId();
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, pDJ->glEBOid);
		glBufferData(GL_ELEMENT_ARRAY_BUFFER, totalIndexesN * sizeof(GLushort), indexBuffer, GL_STATIC_DRAW);
		delete[] indexBuffer;
		pDJ->pointsN = totalIndexesN;
	}
	//create and fill vertex attributes array (VAO)
	pDJ->buildVAO();
	return 1;
}

int ModelBuilder1base::rearrangeArraysForDrawJob(ModelBuilder1base* pMB, std::vector<Vertex01*> allVertices, std::vector<Vertex01*> useVertices, std::vector<Triangle01*> useTriangles) {
	int totalTrianglesN = useTriangles.size();
	if (totalTrianglesN < 1)
		return 0;
	int totalVerticesN = useVertices.size();
	//save new vertices order in original vertices array
	//since triangles indices refer to original vertices order
	for (int i = 0; i < totalVerticesN; i++) {
		Vertex01* pVX1 = useVertices.at(i);
		Vertex01* pVX0 = allVertices.at(pVX1->altN);
		pVX0->altN = i;
	}
	//replace triangle original indices by new numbers saved in original vertices altN
	for (int tN = 0; tN < totalTrianglesN; tN++) {
		Triangle01* pTR = useTriangles.at(tN);
		for (int i = 0; i < 3; i++) {
			Vertex01* pVX0 = allVertices.at(pTR->idx[i]);
			pTR->idx[i] = pVX0->altN;
		}
	}
	return 1;
}

int ModelBuilder1base::moveGroupDg(ModelBuilder1base* pMB, float aX, float aY, float aZ, float kX, float kY, float kZ) {
	//moves and rotates vertex group
	//rotation angles are set in degrees
	mat4x4 transformMatrix = { 1,0,0,0, 0,1,0,0, 0,0,1,0, 0,0,0,1 };
	mat4x4_translate(transformMatrix, kX, kY, kZ);
	//rotation order: Z-X-Y
	if (aY != 0) mat4x4_rotate_Y(transformMatrix, transformMatrix, degrees2radians * aY);
	if (aX != 0) mat4x4_rotate_X(transformMatrix, transformMatrix, degrees2radians * aX);
	if (aZ != 0) mat4x4_rotate_Z(transformMatrix, transformMatrix, degrees2radians * aZ);

	int vertsN = pMB->vertices.size();
	for (int i = pMB->pCurrentGroup->fromVertexN; i < vertsN; i++) {
		Vertex01* pVX = pMB->vertices.at(i);
		mat4x4_mul_vec4plus(pVX->aPos, transformMatrix, pVX->aPos, 1);
		mat4x4_mul_vec4plus(pVX->aNormal, transformMatrix, pVX->aNormal, 0);
	}
	return 1;
}

И наконец, TheGame.cpp

10. Заменим TheGame.cpp код на:

#include "TheGame.h"
#include "platform.h"
#include "utils.h"
#include "linmath.h"
#include "Texture.h"
#include "Shader.h"
#include "DrawJob.h"
#include "ModelBuilder.h"
#include "TexCoords.h"

extern std::string filesRoot;
extern float degrees2radians;

std::vector<GameSubj*> TheGame::gameSubjs;

int TheGame::getReady() {
    bExitGame = false;
    Shader::loadShaders();
    glEnable(GL_CULL_FACE);

    //=== create box ========================
    GameSubj* pGS = new GameSubj();
    gameSubjs.push_back(pGS);

    pGS->name.assign("box1");
    pGS->ownCoords.setPosition(0, 0, 0);
    pGS->ownCoords.setDegrees(0, 0, 0);
    pGS->ownSpeed.setDegrees(0,3,0);

    ModelBuilder* pMB = new ModelBuilder();
    pMB->useSubjN(gameSubjs.size() - 1);

    //define VirtualShape
    VirtualShape vs;
    vs.setShapeType("box-tank");
    vs.whl[0] = 60;
    vs.whl[1] = 160;
    vs.whl[2] = 390;
    vs.setExt(20);
    vs.extD = 0;
    vs.extF = 0; //to make front face "flat"
    vs.sectionsR = 2;

    Material mt;
    //define material - gold
    mt.setShaderType("mirror");
    mt.uTex0 = Texture::loadTexture(filesRoot + "/dt/common/img/whitenoise/wn64_blur3.bmp"); //white noise
    mt.uTex0translateChannelN = 0;
    mt.uTex3 = Texture::loadTexture(filesRoot + "/dt/common/img/materials/gold01.bmp");
    pMB->useMaterial(&mt);

    pMB->buildBoxFace(pMB,"front v", &vs);
    pMB->buildBoxFace(pMB, "back v", &vs);
    pMB->buildBoxFace(pMB, "top", &vs);
    pMB->buildBoxFace(pMB, "bottom", &vs);
    pMB->buildBoxFace(pMB, "left all", &vs);

    //textured surface
    mt.clear(); // set to zero;
    mt.setShaderType("phong");
    mt.uTex0 = Texture::loadTexture(filesRoot + "/dt/sample_img.png"); //sample img
    //transparency map
    mt.uTex1mask = Texture::loadTexture(filesRoot + "/dt/common/img/whitenoise/wn64_blur1.bmp"); //white noise
    mt.uTex1alphaChannelN = 0;
    pMB->useMaterial(&mt);
    TexCoords tc;
    tc.set(mt.uTex0, 11, 12, 256, 128, "h"); //flip horizontally
    pMB->buildBoxFace(pMB, "right all", &vs, &tc);

    pMB->buildDrawJobs(gameSubjs);

    delete pMB;

    //===== set up camera
    mainCamera.ownCoords.setDegrees(15, 180, 0); //set camera angles/orientation
    mainCamera.viewRangeDg = 30;
    mainCamera.stageSize[0] = 500;
    mainCamera.stageSize[1] = 375;
    memcpy(mainCamera.lookAtPoint, pGS->ownCoords.pos, sizeof(float) * 3);
    mainCamera.onScreenResize();

    //===== set up light
    v3set(dirToMainLight, -1, 1, 1);
    vec3_norm(dirToMainLight, dirToMainLight);

    return 1;
}
int TheGame::drawFrame() {
    myPollEvents();

    //glClearColor(0.0, 0.0, 0.5, 1.0);
    glClear(GL_COLOR_BUFFER_BIT);

    //calculate halfVector
    float dirToCamera[4] = { 0,0,-1,0 }; //-z
    mat4x4_mul_vec4plus(dirToCamera, *mainCamera.ownCoords.getRotationMatrix(), dirToCamera, 0);

    float uHalfVector[4] = { 0,0,0,0 };
    for (int i = 0; i < 3; i++)
        uHalfVector[i] = (dirToCamera[i] + dirToMainLight[i]) / 2;
    vec3_norm(uHalfVector, uHalfVector);

    mat4x4 mProjection, mViewProjection, mMVP, mMV4x4;
    //mat4x4_ortho(mProjection, -(float)screenSize[0] / 2, (float)screenSize[0] / 2, -(float)screenSize[1] / 2, (float)screenSize[1] / 2, 100.f, 500.f);
    float nearClip = mainCamera.focusDistance - 250;
    float farClip = mainCamera.focusDistance + 250;
    mat4x4_perspective(mProjection, mainCamera.viewRangeDg * degrees2radians, screenAspectRatio, nearClip, farClip);
    mat4x4_mul(mViewProjection, mProjection, mainCamera.lookAtMatrix);
    //mViewProjection[1][3] = 0; //keystone effect

    //scan subjects
    int subjsN = gameSubjs.size();
    for (int subjN = 0; subjN < subjsN; subjN++) {
        GameSubj* pGS = gameSubjs.at(subjN);
        //behavior - apply rotation speed
        pGS->moveSubj();
        //prepare subject for rendering
        pGS->buildModelMatrix(pGS);
        //build MVP matrix for given subject
        mat4x4_mul(mMVP, mViewProjection, pGS->ownModelMatrix);
        //build Model-View (rotation) matrix for normals
        mat4x4_mul(mMV4x4, mainCamera.lookAtMatrix, (vec4*)pGS->ownCoords.getRotationMatrix());
        //convert to 3x3 matrix
        float mMV3x3[3][3];
        for (int y = 0; y < 3; y++)
            for (int x = 0; x < 3; x++)
                mMV3x3[y][x] = mMV4x4[y][x];
        //render subject
        for (int i = 0; i < pGS->djTotalN; i++) {
            DrawJob* pDJ = DrawJob::drawJobs.at(pGS->djStartN + i);
            pDJ->execute((float*)mMVP, *mMV3x3, dirToMainLight, uHalfVector, NULL);
        }
    }
    //synchronization
    while (1) {
        long long int currentMillis = getSystemMillis();
        long long int millisSinceLastFrame = currentMillis - lastFrameMillis;
        if (millisSinceLastFrame >= millisPerFrame) {
            lastFrameMillis = currentMillis;
            break;
        }
    }
    mySwapBuffers();
    return 1;
}

int TheGame::cleanUp() {
    int itemsN = gameSubjs.size();
    //delete all UISubjs
    for (int i = 0; i < itemsN; i++) {
        GameSubj* pGS = gameSubjs.at(i);
        delete pGS;
    }
    gameSubjs.clear();
    //clear all other classes
    Texture::cleanUp();
    Shader::cleanUp();
    DrawJob::cleanUp();
    return 1;
}
int TheGame::onScreenResize(int width, int height) {
    if (screenSize[0] == width && screenSize[1] == height)
        return 0;
    screenSize[0] = width;
    screenSize[1] = height;
    screenAspectRatio = (float)width / height;
    glViewport(0, 0, width, height);
    mainCamera.onScreenResize();
    mylog(" screen size %d x %d\n", width, height);
    return 1;
}
int TheGame::run() {
    getReady();
    while (!bExitGame) {
        drawFrame();
    }
    cleanUp();
    return 1;
}

Заметим, что теперь мы задаем Materials по-другому:

  • Вместо номеров шейдеров, мы теперь задаем желаемый тип шейдера (строки 46 и 60). Конкретный номер будет выбран позже программно, при создании DrawJob.
  • Определение “gold” материала, строки 46-50: Главная текстура uTex0 – белый шум. Мы возьмем черно-белый канал #0 и переведем полученное 0-to-1 значение в цвет из 4×1 текстуры uTex3, которая установлена в gold01.bmp.
  • Маска прозрачности (трафарет), строки 62-64: Мы устанавливаем uTex1mask в изображение белого шума. Задавать uTex1alphaChannelN не обязательно. По умолчанию это 3 – Alpha-channel.
  • И, конечно, мы возвращаемся к нормальной run().

11. Компиляция и запуск:

  • Черные дыры на текстурированной стороне – от Transparency Mask.

На Андроиде тоже проверено.

Direct fit!

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