Initial commit

1 files changed, 286 insertions, 0 deletions

diff --git a/src/graphics/shader.cpp b/src/graphics/shader.cpp
new file mode 100644
index 0000000..6ac9949
--- /dev/null
+++ b/src/graphics/shader.cpp
@@ -0,0 +1,286 @@
+#include "shader.h"
+
+#include <QFile>
+#include <QString>
+#include <QTextStream>
+#include <algorithm>
+#include <iostream>
+#include <utility>
+
+#include "graphicsdebug.h"
+
+Shader::Shader(const std::string &vertexPath, const std::string &fragmentPath)
+{
+    createProgramID();
+    std::vector<GLuint> shaders;
+    shaders.push_back(createVertexShaderFromSource(getFileContents(vertexPath)));
+    shaders.push_back(createFragmentShaderFromSource(getFileContents(fragmentPath)));
+    buildShaderProgramFromShaders(shaders);
+    discoverShaderData();
+}
+
+Shader::Shader(const std::string &vertexPath, const std::string &geometryPath, const std::string &fragmentPath) {
+    createProgramID();
+    std::vector<GLuint> shaders;
+    shaders.push_back(createVertexShaderFromSource(getFileContents(vertexPath)));
+    shaders.push_back(createGeometryShaderFromSource(getFileContents(geometryPath)));
+    shaders.push_back(createFragmentShaderFromSource(getFileContents(fragmentPath)));
+    buildShaderProgramFromShaders(shaders);
+    discoverShaderData();
+}
+
+Shader::~Shader()
+{
+    glDeleteProgram(m_programID);
+}
+
+Shader::Shader(Shader &&that) :
+    m_programID(that.m_programID),
+    m_attributes(std::move(that.m_attributes)),
+    m_uniforms(std::move(that.m_uniforms))
+{
+    that.m_programID = 0;
+}
+
+Shader& Shader::operator=(Shader &&that) {
+    this->~Shader();
+
+    m_programID = that.m_programID;
+    m_attributes = std::move(that.m_attributes);
+    m_uniforms = std::move(that.m_uniforms);
+
+    that.m_programID = 0;
+
+    return *this;
+}
+
+void Shader::bind() const {
+    glUseProgram(m_programID);
+}
+
+void Shader::unbind() const {
+    glUseProgram(0);
+}
+
+GLuint Shader::getUniformLocation(std::string name) {
+    return glGetUniformLocation(m_programID, name.c_str());
+}
+
+GLuint Shader::getEnumeratedUniformLocation(std::string name, int index) {
+    std::string n = name + "[" + std::to_string(index) + "]";
+    return glGetUniformLocation(m_programID, n.c_str());
+}
+
+void Shader::setUniform(const std::string &name, float f) {
+    glUniform1f(m_uniforms[name], f);
+}
+
+void Shader::setUniform(const std::string &name, int i) {
+    glUniform1i(m_uniforms[name], i);
+}
+
+void Shader::setUniform(const std::string &name, bool b) {
+    glUniform1i(m_uniforms[name], static_cast<GLint>(b));
+}
+
+void Shader::setUniformArrayByIndex(const std::string &name, float f, size_t index) {
+    glUniform1f(m_uniformArrays[std::make_tuple(name, index)], f);
+}
+
+void Shader::setUniformArrayByIndex(const std::string &name, int i, size_t index) {
+    glUniform1i(m_uniformArrays[std::make_tuple(name, index)], i);
+}
+
+void Shader::setUniformArrayByIndex(const std::string &name, bool b, size_t index) {
+    glUniform1i(m_uniformArrays[std::make_tuple(name, index)], static_cast<GLint>(b));
+}
+
+void Shader::attachShaders(const std::vector<GLuint> &shaders) {
+    std::for_each(shaders.begin(), shaders.end(), [this](int s){ glAttachShader(m_programID, s); });
+}
+
+void Shader::buildShaderProgramFromShaders(const std::vector<GLuint> &shaders) {
+    attachShaders(shaders);
+    linkShaderProgram();
+    detachShaders(shaders);
+    deleteShaders(shaders);
+}
+
+GLuint Shader::createFragmentShaderFromSource(const std::string &source) {
+   return createShaderFromSource(source, GL_FRAGMENT_SHADER);
+}
+
+GLuint Shader::createGeometryShaderFromSource(const std::string &source) {
+    return createShaderFromSource(source, GL_GEOMETRY_SHADER);
+}
+
+void Shader::compileShader(GLuint handle, const std::string &source) {
+    const GLchar* codeArray[] = { source.c_str() };
+    glShaderSource(handle, 1, codeArray, nullptr);
+    glCompileShader(handle);
+}
+
+GLuint Shader::createVertexShaderFromSource(const std::string &source) {
+    return createShaderFromSource(source, GL_VERTEX_SHADER);
+}
+
+GLuint Shader::createShaderFromSource(const std::string &source, GLenum shaderType) {
+    GLuint shaderHandle = glCreateShader(shaderType);
+    compileShader(shaderHandle, source);
+    checkShaderCompilationStatus(shaderHandle);
+    return shaderHandle;
+}
+
+void Shader::createProgramID() {
+    m_programID = glCreateProgram();
+}
+
+void Shader::detachShaders(const std::vector<GLuint> &shaders) {
+    std::for_each(shaders.begin(), shaders.end(), [this](int s){ glDetachShader(m_programID, s); });
+}
+
+void Shader::deleteShaders(const std::vector<GLuint> &shaders) {
+    std::for_each(shaders.begin(), shaders.end(), [](int s){ glDeleteShader(s); });
+}
+
+void Shader::linkShaderProgram() {
+    glLinkProgram(m_programID);
+    checkShaderLinkStatus(m_programID);
+}
+
+void Shader::discoverShaderData() {
+    discoverAttributes();
+    discoverUniforms();
+}
+
+void Shader::discoverAttributes() {
+    bind();
+    GLint attribCount;
+    glGetProgramiv(m_programID, GL_ACTIVE_ATTRIBUTES, &attribCount);
+    for (int i = 0; i < attribCount; i++) {
+        const GLsizei bufSize = 256;
+        GLsizei nameLength = 0;
+        GLint arraySize = 0;
+        GLenum type;
+        GLchar name[bufSize];
+        glGetActiveAttrib(m_programID, i, bufSize, &nameLength, &arraySize, &type, name);
+        name[std::min(nameLength, bufSize - 1)] = 0;
+        m_attributes[std::string(name)] = glGetAttribLocation(m_programID, name);
+    }
+    unbind();
+}
+
+void Shader::discoverUniforms() {
+    bind();
+    GLint uniformCount;
+    glGetProgramiv(m_programID, GL_ACTIVE_UNIFORMS, &uniformCount);
+    for (int i = 0; i < uniformCount; i++) {
+        const GLsizei bufSize = 256;
+        GLsizei nameLength = 0;
+        GLint arraySize = 0;
+        GLenum type;
+        GLchar name[bufSize];
+        glGetActiveUniform(m_programID, i, bufSize, &nameLength, &arraySize, &type, name);
+        name[std::min(nameLength, bufSize - 1)] = 0;
+
+        std::string strname(name);
+        if (isUniformArray(name, nameLength)) {
+            addUniformArray(strname, arraySize);
+        } else if (isTexture(type)) {
+            addTexture(strname);
+        } else {
+            addUniform(strname);
+        }
+    }
+    unbind();
+}
+
+bool Shader::isUniformArray(const GLchar *name, GLsizei nameLength) {
+    // Check if the last 3 characters are '[0]'
+    return (name[nameLength - 3] == '[') &&
+           (name[nameLength - 2] == '0') &&
+           (name[nameLength - 1] == ']');
+}
+
+bool Shader::isTexture(GLenum type) {
+    return (type == GL_SAMPLER_2D) ||
+           (type == GL_SAMPLER_CUBE);
+}
+
+void Shader::addUniformArray(const std::string &name, size_t size) {
+    std::string cleanName = name.substr(0, name.length() - 3);
+    for (auto i = static_cast<size_t>(0); i < size; i++) {
+        std::string enumeratedName = name;
+        enumeratedName[enumeratedName.length() - 2] = static_cast<char>('0' + i);
+        std::tuple< std::string, size_t > nameIndexTuple = std::make_tuple(cleanName, i);
+        m_uniformArrays[nameIndexTuple] = glGetUniformLocation(m_programID, enumeratedName.c_str());
+    }
+
+#if GRAPHICS_DEBUG_LEVEL > 0
+    m_trackedUniformArrays[name] = false;
+#endif
+}
+
+void Shader::addTexture(const std::string &name) {
+    GLint location = glGetUniformLocation(m_programID, name.c_str());
+    m_textureLocations[name] = location;
+    GLint slot = m_textureSlots.size();
+    m_textureSlots[location] = slot; // Assign slots in increasing order.
+
+#if GRAPHICS_DEBUG_LEVEL > 0
+    m_trackedTextures[name] = false;
+#endif
+}
+
+void Shader::addUniform(const std::string &name) {
+    m_uniforms[name] = glGetUniformLocation(m_programID, name.c_str());
+
+#if GRAPHICS_DEBUG_LEVEL > 0
+    m_trackedUniforms[name] = false;
+#endif
+}
+
+bool Shader::printDebug() {
+    bool noErrors = true;
+
+    for (auto &pair : m_trackedUniforms) {
+        if (!pair.second) {
+            std::cerr << "Uniform '" << pair.first << "' was not set." << std::endl;
+            noErrors = false;
+        }
+    }
+
+    for (auto &pair : m_trackedTextures) {
+        if (!pair.second) {
+            std::cerr << "Texture '" << pair.first << "' was not set." << std::endl;
+            noErrors = false;
+        }
+    }
+
+    return noErrors;
+}
+
+void Shader::resetDebug() {
+    for (auto &pair : m_trackedUniforms) {
+        m_trackedUniforms[pair.first] = false;
+    }
+
+    for (auto &pair : m_trackedTextures) {
+        m_trackedTextures[pair.first] = false;
+    }
+}
+
+std::string Shader::getFileContents(std::string path)
+{
+    QString qpath = QString::fromStdString(path);
+    QFile file(qpath);
+
+    if (file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        QTextStream stream(&file);
+        QString contents = stream.readAll();
+        file.close();
+        return contents.toStdString();
+    }
+    return "";
+}
+