static void
gst_gl_transformation_build_mvp (GstGLTransformation * transformation)
{
graphene_point3d_t translation_vector =
GRAPHENE_POINT3D_INIT (transformation->xtranslation * 2.0 *
transformation->aspect,
transformation->ytranslation * 2.0,
transformation->ztranslation * 2.0);
graphene_matrix_t model_matrix;
graphene_matrix_t projection_matrix;
graphene_matrix_t view_matrix;
graphene_matrix_t vp_matrix;
graphene_vec3_t eye;
graphene_vec3_t center;
graphene_vec3_t up;
graphene_vec3_init (&eye, 0.f, 0.f, 1.f);
graphene_vec3_init (¢er, 0.f, 0.f, 0.f);
graphene_vec3_init (&up, 0.f, 1.f, 0.f);
graphene_matrix_init_scale (&model_matrix,
transformation->xscale, transformation->yscale, 1.0f);
graphene_matrix_rotate (&model_matrix,
transformation->xrotation, graphene_vec3_x_axis ());
graphene_matrix_rotate (&model_matrix,
transformation->yrotation, graphene_vec3_y_axis ());
graphene_matrix_rotate (&model_matrix,
transformation->zrotation, graphene_vec3_z_axis ());
graphene_matrix_translate (&model_matrix, &translation_vector);
if (transformation->ortho) {
graphene_matrix_init_ortho (&projection_matrix,
-transformation->aspect, transformation->aspect,
-1, 1, transformation->znear, transformation->zfar);
} else {
graphene_matrix_init_perspective (&projection_matrix,
transformation->fov,
transformation->aspect, transformation->znear, transformation->zfar);
}
graphene_matrix_init_look_at (&view_matrix, &eye, ¢er, &up);
graphene_matrix_multiply (&view_matrix, &projection_matrix, &vp_matrix);
graphene_matrix_multiply (&model_matrix, &vp_matrix,
&transformation->mvp_matrix);
}
// The MAIN function, from here we start the application and run the game loop
int main()
{
// Init GLFW
glfwInit();
// Set all the required options for GLFW
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
// Create a GLFWwindow object that we can use for GLFW's functions
GLFWwindow* window = glfwCreateWindow(WIDTH, HEIGHT, "LearnOpenGL", NULL, NULL);
glfwMakeContextCurrent(window);
// Set the required callback functions
glfwSetKeyCallback(window, key_callback);
// Set this to true so GLEW knows to use a modern approach to retrieving function pointers and extensions
glewExperimental = GL_TRUE;
// Initialize GLEW to setup the OpenGL Function pointers
glewInit();
// Define the viewport dimensions
glViewport(0, 0, WIDTH, HEIGHT);
// Setup OpenGL options
glEnable(GL_DEPTH_TEST);
// Build and compile our shader program
shader our_shader = shader_new("shader.vs", "shader.frag");
// Set up vertex data (and buffer(s)) and attribute pointers
GLfloat vertices[] = {
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f,
0.5f, -0.5f, -0.5f, 1.0f, 0.0f,
0.5f, 0.5f, -0.5f, 1.0f, 1.0f,
0.5f, 0.5f, -0.5f, 1.0f, 1.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f,
0.5f, -0.5f, 0.5f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 1.0f,
0.5f, 0.5f, 0.5f, 1.0f, 1.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 1.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f,
-0.5f, 0.5f, 0.5f, 1.0f, 0.0f,
-0.5f, 0.5f, -0.5f, 1.0f, 1.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f,
-0.5f, 0.5f, 0.5f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f,
0.5f, 0.5f, -0.5f, 1.0f, 1.0f,
0.5f, -0.5f, -0.5f, 0.0f, 1.0f,
0.5f, -0.5f, -0.5f, 0.0f, 1.0f,
0.5f, -0.5f, 0.5f, 0.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f,
0.5f, -0.5f, -0.5f, 1.0f, 1.0f,
0.5f, -0.5f, 0.5f, 1.0f, 0.0f,
0.5f, -0.5f, 0.5f, 1.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f,
0.5f, 0.5f, -0.5f, 1.0f, 1.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f
};
// World space positions of our cubes
graphene_point3d_t cubePositions[] = {
GRAPHENE_POINT3D_INIT(0.0f, 0.0f, 0.0f),
GRAPHENE_POINT3D_INIT( 2.0f, 5.0f, -15.0f),
GRAPHENE_POINT3D_INIT(-1.5f, -2.2f, -2.5f),
GRAPHENE_POINT3D_INIT(-3.8f, -2.0f, -12.3f),
GRAPHENE_POINT3D_INIT( 2.4f, -0.4f, -3.5f),
GRAPHENE_POINT3D_INIT(-1.7f, 3.0f, -7.5f),
GRAPHENE_POINT3D_INIT( 1.3f, -2.0f, -2.5f),
GRAPHENE_POINT3D_INIT( 1.5f, 2.0f, -2.5f),
GRAPHENE_POINT3D_INIT( 1.5f, 0.2f, -1.5f),
GRAPHENE_POINT3D_INIT(-1.3f, 1.0f, -1.5f)
};
GLuint VBO, VAO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
// Position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);
// TexCoord attribute
glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
glEnableVertexAttribArray(2);
glBindVertexArray(0); // Unbind VAO
// Load and create a texture
GLuint texture1;
GLuint texture2;
// ====================
// Texture 1
// ====================
glGenTextures(1, &texture1);
glBindTexture(GL_TEXTURE_2D, texture1); // All upcoming GL_TEXTURE_2D operations now have effect on our texture object
// Set our texture parameters
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); // Set texture wrapping to GL_REPEAT
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
// Set texture filtering
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Load, create texture and generate mipmaps
int width, height;
unsigned char* image = SOIL_load_image("container.jpg", &width, &height, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
glBindTexture(GL_TEXTURE_2D, 0); // Unbind texture when done, so we won't accidentily mess up our texture.
// ===================
// Texture 2
// ===================
glGenTextures(1, &texture2);
glBindTexture(GL_TEXTURE_2D, texture2);
// Set our texture parameters
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
// Set texture filtering
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Load, create texture and generate mipmaps
image = SOIL_load_image("awesomeface.png", &width, &height, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
glBindTexture(GL_TEXTURE_2D, 0);
// Game loop
while (!glfwWindowShouldClose(window))
{
// Check if any events have been activiated (key pressed, mouse moved etc.) and call corresponding response functions
glfwPollEvents();
// Render
// Clear the colorbuffer
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// Bind Textures using texture units
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(glGetUniformLocation(our_shader.program, "ourTexture1"), 0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture2);
glUniform1i(glGetUniformLocation(our_shader.program, "ourTexture2"), 1);
// Activate shader
shader_use(&our_shader);
// Create transformations
graphene_matrix_t view;
graphene_point3d_t view_point;
graphene_matrix_init_translate(&view, graphene_point3d_init(&view_point, 0.0f, 0.0f, -3.0f));
graphene_matrix_t projection;
graphene_matrix_init_perspective(&projection, 45.0f, (GLfloat) WIDTH / (GLfloat) HEIGHT, 0.1f, 100.0f);
// Get their uniform location
GLint modelLoc = glGetUniformLocation(our_shader.program, "model");
GLint viewLoc = glGetUniformLocation(our_shader.program, "view");
GLint projLoc = glGetUniformLocation(our_shader.program, "projection");
// Pass the matrices to the shader
GLfloat view_f[16] = {};
graphene_matrix_to_float(&view, view_f);
GLfloat proj_f[16] = {};
graphene_matrix_to_float(&projection, proj_f);
glUniformMatrix4fv(viewLoc, 1, GL_FALSE, view_f);
// Note: currently we set the projection matrix each frame, but since the projection matrix rarely changes it's often best practice to set it outside the main loop only once.
glUniformMatrix4fv(projLoc, 1, GL_FALSE, proj_f);
glBindVertexArray(VAO);
for (GLuint i = 0; i < 10; i++)
{
// Calculate the model matrix for each object and pass it to shader before drawing
graphene_matrix_t model;
graphene_matrix_init_translate(&model, &cubePositions[i]);
GLfloat angle = 5.0f * i;
graphene_vec3_t axis;
graphene_vec3_init(&axis, -1.3f, 1.0f, -1.5f);
graphene_matrix_rotate(&model, angle, &axis);
GLfloat model_f[16] = {};
graphene_matrix_to_float(&model, model_f);
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, model_f);
glDrawArrays(GL_TRIANGLES, 0, 36);
}
glBindVertexArray(0);
// Swap the screen buffers
glfwSwapBuffers(window);
}
// Properly de-allocate all resources once they've outlived their purpose
glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);
// Terminate GLFW, clearing any resources allocated by GLFW.
glfwTerminate();
return 0;
}
