Fix ortho projection, sprite vertex to map from 0 to 1

src/Game.cpp

@@ -31,28 +31,21 @@ void Game::init()
 	                                        "awesomeface");
 	Dengine::AssetManager::loadTextureImage("data/textures/plain_terrain.jpg",
 	                                        "plain_terrain");
-	glCheckError();
-
-	glm::mat4 projection= glm::ortho(0.0f, 1280.0f,
-	               720.0f, 0.0f, -1.0f, 1.0f);
-	glCheckError();
 
 	this->shader = Dengine::AssetManager::getShader("sprite");
 	this->shader->use();
-	glCheckError();
-	//shader->uniformSetMat4fv("projection", projection);
-	glCheckError();
+
+	glm::mat4 projection =
+	    glm::ortho(0.0f, static_cast<GLfloat>(this->width), 0.0f,
+	               static_cast<GLfloat>(this->height), 0.0f, 1.0f);
+	this->shader->uniformSetMat4fv("projection", projection);
 
 	GLuint projectionLoc = glGetUniformLocation(this->shader->id, "projection");
-	glCheckError();
 	glUniformMatrix4fv(projectionLoc, 1, GL_FALSE, glm::value_ptr(projection));
-	glCheckError();
 
 	/* Init game state */
 	this->state = GAME_ACTIVE;
-	glCheckError();
 	this->renderer = new Dengine::Renderer(this->shader);
-	glCheckError();
 }
 
 void Game::processInput(const f32 dt) {}
@@ -61,14 +54,13 @@ void Game::render()
 {
 	const Dengine::Texture *tex =
 	    Dengine::AssetManager::getTexture("plain_terrain");
-	glm::vec2 pos = glm::vec2(200, 200);
-	glm::vec2 size = glm::vec2(640, 360);
-	GLfloat rotation = 0;
-	glm::vec3 color = glm::vec3(1.0f);
-	this->renderer->drawSprite(tex, pos, size, rotation, color);
+	glm::vec2 pos  = glm::vec2(0, 0);
+	glm::vec2 size = glm::vec2(1280.0f, 720.0f);
+	this->renderer->drawSprite(tex, pos, size);
 
-	this->renderer->drawSprite(Dengine::AssetManager::getTexture("awesomeface"),
-	                           glm::vec2(200, 200), glm::vec2(300, 400), 45.0f,
-	                           glm::vec3(0.0f, 1.0f, 0.0f));
+	tex  = Dengine::AssetManager::getTexture("container");
+	pos  = glm::vec2(200, 200);
+	size = glm::vec2(250.0f, 250.0f);
+	this->renderer->drawSprite(tex, pos, size);
 }
 }

src/Renderer.cpp

@@ -1,6 +1,7 @@
 #include <Dengine/Renderer.h>
 #include <Dengine/OpenGL.h>
 
+#include <glm/gtx/transform.hpp>
 #include <glm/gtc/matrix_transform.hpp>
 
 namespace Dengine
@@ -19,21 +20,14 @@ void Renderer::drawSprite(const Texture *texture, glm::vec2 position,
                           glm::vec2 size, GLfloat rotate, glm::vec3 color)
 {
 	this->shader->use();
-	glm::mat4 model;
-	// First translate (transformations are: scale happens first, then rotation
-	// and then finall translation happens; reversed order)
-	model = glm::translate(model, glm::vec3(position, 0.0f));
+	glm::mat4 transMatrix  = glm::translate(glm::vec3(position, 0.0f));
+	glm::mat4 rotateMatrix = glm::rotate(rotate, glm::vec3(0.0f, 0.0f, 1.0f));
 
-	// Move origin of rotation to center of quad
-	model = glm::translate(model, glm::vec3(0.5f * size.x, 0.5f * size.y, 0.0f));
 
-	// Then rotate
-	model = glm::rotate(model, rotate, glm::vec3(0.0f, 0.0f, 1.0f));
+	// NOTE(doyle): We draw everything as a unit square in OGL. Scale it to size
+	glm::mat4 scaleMatrix  = glm::scale(glm::vec3(size, 1.0f));
 
-	// Move origin back
-	model = glm::translate(model, glm::vec3(-0.5f * size.x, -0.5f * size.y, 0.0f));
-
-	model = glm::scale(model, glm::vec3(size, 1.0f)); // Last scale
+	glm::mat4 model = transMatrix * rotateMatrix * scaleMatrix;
 
 	this->shader->uniformSetMat4fv("model", model);
 
@@ -51,12 +45,14 @@ void Renderer::drawSprite(const Texture *texture, glm::vec2 position,
 
 void Renderer::initRenderData()
 {
+	// NOTE(doyle): Draws a series of triangles (three-sided polygons) using
+	// vertices v0, v1, v2, then v2, v1, v3 (note the order)
 	glm::vec4 vertices[] = {
 	    //  x     y       s     t
-	    {+1.0f, +1.0f, 1.0f, 1.0f}, // Top right
-	    {+1.0f, -1.0f, 1.0f, 0.0f}, // Bottom right
-	    {-1.0f, +1.0f, 0.0f, 1.0f}, // Top left
-	    {-1.0f, -1.0f, 0.0f, 0.0f}, // Bottom left
+	    {0.0f, 1.0f, 0.0f, 1.0f}, // Top left
+	    {0.0f, 0.0f, 0.0f, 0.0f}, // Bottom left
+	    {1.0f, 1.0f, 1.0f, 1.0f}, // Top right
+	    {1.0f, 0.0f, 1.0f, 0.0f}, // Bottom right
 	};
 
 	GLuint VBO;

src/dengine.cpp

@@ -79,8 +79,6 @@ int main()
 	// regardless of success. Catch it once by calling glGetError
 	glGetError();
 
-	glCheckError();
-
 	glm::ivec2 frameBufferSize;
 	glfwGetFramebufferSize(window, &frameBufferSize.x, &frameBufferSize.y);
 	glViewport(0, 0, frameBufferSize.x, frameBufferSize.y);
@@ -91,22 +89,15 @@ int main()
 
 	glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
 	glEnable(GL_BLEND);
-	glCheckError();
 	glEnable(GL_CULL_FACE);
-	glCheckError();
 
 	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-	glCheckError();
 	glCullFace(GL_BACK);
-	glCheckError();
 
 	Breakout::Game game = Breakout::Game(frameBufferSize.x, frameBufferSize.y);
-	glCheckError();
 	game.init();
-	glCheckError();
 
 	glfwSetWindowUserPointer(window, static_cast<void *>(&game));
-	glCheckError();
 
 	f32 deltaTime = 0.0f; // Time between current frame and last frame
 	f32 lastFrame = 0.0f; // Time of last frame