more incomplete gl stuff

CMakeLists.txt

@@ -42,3 +42,6 @@ endfunction()
 
 add_subdirectory(externals)
 add_subdirectory(src)
+
+
+set_property(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} PROPERTY VS_STARTUP_PROJECT glTests)

src/CMakeLists.txt

@@ -3,3 +3,4 @@ include_directories(.)
 
 add_subdirectory(common)
 add_subdirectory(LegacyRayTracer)
+add_subdirectory(glTests)

src/glTests/CMakeLists.txt

@@ -0,0 +1,8 @@
+add_executable(glTests
+    main.cpp
+)
+
+create_target_directory_groups(glTests)
+
+target_link_libraries(glTests PRIVATE common)
+target_link_libraries(glTests PRIVATE glad glfw)

src/glTests/main.cpp

@@ -0,0 +1,144 @@
+#include <iostream>
+
+#include <glad/glad.h>
+
+#include <GLFW/glfw3.h>
+
+static unsigned int CompileShader(unsigned int type, const std::string& source) {
+    const unsigned int id = glCreateShader(type);
+    const char* src = source.c_str();
+    glShaderSource(id, 1, &src, nullptr);
+    glCompileShader(id);
+
+    int result;
+    glGetShaderiv(id, GL_COMPILE_STATUS, &result);
+    if (result == GL_FALSE) {
+        int length;
+        glGetShaderiv(id, GL_INFO_LOG_LENGTH, &length);
+        char* message = new char[length];
+        glGetShaderInfoLog(id, length, &length, message);
+        std::cout << "Failed to compile " << (type == GL_VERTEX_SHADER ? "vertex" : "fragment") << std::endl;
+        std::cout << message << std::endl;
+        glDeleteShader(id);
+        delete[] message;
+        return 0;
+    }
+
+    return id;
+}
+
+static unsigned int CreateShader(const std::string& vertexShader, const std::string& fragmentShader) {
+    const unsigned int program = glCreateProgram();
+    unsigned int vs = CompileShader(GL_VERTEX_SHADER, vertexShader);
+    unsigned int fs = CompileShader(GL_FRAGMENT_SHADER, fragmentShader);
+
+    glAttachShader(program, vs);
+    glAttachShader(program, fs);
+    glLinkProgram(program);
+    glValidateProgram(program);
+
+    glDeleteShader(vs);
+    glDeleteShader(fs);
+
+    return program;
+}
+
+int main(void) {
+    GLFWwindow* window;
+
+    /* Initialize the library */
+    if (!glfwInit())
+        return -1;
+
+    /* Create a windowed mode window and its OpenGL context */
+    window = glfwCreateWindow(640, 480, "Hello World", NULL, NULL);
+    if (!window)
+    {
+        glfwTerminate();
+        return -1;
+    }
+
+    /* Make the window's context current */
+    glfwMakeContextCurrent(window);
+
+    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
+    {
+        std::cout << "Failed to initialize OpenGL context" << std::endl;
+        return -1;
+    }
+    std::cout << "OpenGL Version " << GLVersion.major << "." << GLVersion.minor << " loaded" << std::endl;
+    std::cout << glGetString(GL_VERSION) << " " << glGetString(GL_VENDOR) << std::endl;
+
+    float positions[] = {
+        -0.5f, -0.5f,
+         0.5f, -0.5f,
+         0.5f, 0.5f,
+        -0.5f, 0.5f
+    };
+
+    unsigned int indicies[] = {
+        0,1,2,
+        2,3,0
+    };
+
+    unsigned int buff;
+    glGenBuffers(1, &buff);
+    glBindBuffer(GL_ARRAY_BUFFER, buff);
+    glBufferData(GL_ARRAY_BUFFER, 8*sizeof(float), positions, GL_STATIC_DRAW);
+
+    glEnableVertexAttribArray(0);
+    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 2 * sizeof(float), 0);
+
+    unsigned int ibo;
+    glGenBuffers(1, &ibo);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, 6*sizeof(unsigned int), indicies, GL_STATIC_DRAW);
+
+    std::string vertexShader = R"(
+#version 330 core
+
+layout(location = 0) in vec4 position;
+
+void main() {
+    gl_Position = position;
+}
+)";
+
+    std::string fragmentShader = R"glsl(
+#version 330 core
+
+layout(location = 0) out vec4 color;
+
+uniform vec4 u_Color;
+
+void main() {
+    color = u_Color;
+}
+)glsl";
+
+    unsigned int shader = CreateShader(vertexShader, fragmentShader);
+    glUseProgram(shader);
+
+    int location = glGetUniformLocation(shader, "u_Color");
+    glUniform4f(location, 0.0f, 0.5f, 0.0f, 1.0f);
+
+    /* Loop until the user closes the window */
+    while (!glfwWindowShouldClose(window))
+    {
+        /* Render here */
+        glClear(GL_COLOR_BUFFER_BIT);
+
+        glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, nullptr);
+
+        /* Swap front and back buffers */
+        glfwSwapBuffers(window);
+
+        /* Poll for and process events */
+        glfwPollEvents();
+    }
+
+    glDeleteProgram(shader);
+
+    glfwTerminate();
+    return 0;
+}