Modified WindowSystem into full render system

This is does because EntityX doesn't guarantee system initialization order

1 files changed, 146 insertions, 0 deletions

diff --git a/src/shader.cpp b/src/shader.cpp
new file mode 100644
index 0000000..bb62ac9
--- /dev/null
+++ b/src/shader.cpp
@@ -0,0 +1,146 @@
+/**
+ * @file shader.cpp
+ *
+ * Copyright (C) 2019  Belle-Isle, Andrew <drumsetmonkey@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <shader.hpp>
+
+#include <fstream>
+#include <iostream>
+#include <vector>
+
+#include <SDL2/SDL.h>
+
+/*************
+*  PRIVATE  *
+*************/
+
+std::string Shader::readShader(std::string filepath)
+{
+    std::string contents = "";
+    std::ifstream file(filepath, std::ios::in);
+
+    if (!file.is_open()) {
+        std::cerr << "Could not read shader " << filepath << 
+                     ". Shader doesn't exist" << std::endl;
+        return "";
+    }
+
+    std::string line = "";
+    while (!file.eof()) {
+        std::getline(file, line);
+        contents.append(line + "\n");
+    }
+
+    file.close();
+    return contents;
+}
+
+GLuint Shader::createShader(std::string filepath, GLenum shaderType)
+{
+    GLuint shader = glCreateShader(shaderType);
+
+    std::string shaderStr = readShader(filepath);
+    const char* shaderSrc = shaderStr.c_str();
+
+    GLint result = GL_FALSE;
+    int logLength;
+
+    glShaderSource(shader, 1, &shaderSrc, NULL);
+    glCompileShader(shader);
+
+    glGetShaderiv(shader, GL_COMPILE_STATUS, &result);
+    glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &logLength);
+    std::vector<char> shaderError((logLength > 1) ? logLength : 1);
+    glGetShaderInfoLog(shader, logLength, NULL, &shaderError[0]);
+    std::cerr << &shaderError[0] << std::endl;
+
+    return shader;
+}
+
+/************
+*  PUBLIC  *
+************/
+
+GLuint Shader::createProgram(std::string vertexPath, std::string fragmentPath)
+{
+    GLuint vertex = createShader(vertexPath, GL_VERTEX_SHADER);
+    GLuint fragment = createShader(fragmentPath, GL_FRAGMENT_SHADER);
+
+    GLuint program = glCreateProgram();
+    glAttachShader(program, vertex);
+    glAttachShader(program, fragment);
+    glLinkProgram(program);
+
+    GLint result = GL_FALSE;
+    int logLength;
+
+    glGetProgramiv(program, GL_COMPILE_STATUS, &result);
+    glGetProgramiv(program, GL_INFO_LOG_LENGTH, &logLength);
+    std::vector<char> programError((logLength > 1) ? logLength : 1);
+    glGetProgramInfoLog(program, logLength, NULL, &programError[0]);
+    std::cerr << &programError[0] << std::endl;
+
+    glDeleteShader(vertex);
+    glDeleteShader(fragment);
+
+    this->program = program;
+
+    return program;
+}
+
+// TODO exceptions
+GLint Shader::addAttribute(std::string attrib)
+{
+    GLint attribute = glGetAttribLocation(program, attrib.c_str());
+
+    if (attribute == -1)
+        SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_ERROR,
+                "Could not bind attribute %s", attrib.c_str());
+
+    attributes.emplace(attrib, attribute);
+    return attribute;
+}
+
+GLint Shader::addUniform(std::string unfi)
+{
+    GLint uniform = glGetUniformLocation(program, unfi.c_str());
+
+    if (uniform == -1)
+        SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_ERROR,
+                "Could not bind uniform %s", unfi.c_str());
+
+    uniforms.emplace(unfi, uniform);
+    return uniform;
+}
+
+// TODO exceptions
+GLint Shader::getAttribute(std::string attrib)
+{
+    return attributes.at(attrib);
+}
+
+GLint Shader::getUniform(std::string unfi)
+{
+    return uniforms.at(unfi);
+}
+
+GLuint Shader::getProgram()
+{
+    return program;
+}
+