feat(renderer) Render player quad with projection

this allows us to render a player controlled entity on screen using a 2D
projection

CMakeLists.txt

@@ -7,7 +7,7 @@ set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 # include directories..
-include_directories(libs)
+include_directories(vendor)
 
 # Deps.
 find_package(SDL3   REQUIRED)

assets/shaders/simple.vert

@@ -2,6 +2,9 @@
 
 layout (location = 0) in vec3 aPos;
 
+uniform mat4 projection;
+uniform mat4 model;
+
 void main() {
-  gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);
+  gl_Position = projection * model * vec4(aPos, 1.0);
 }

src/bettola.cpp

@@ -5,6 +5,9 @@
 #include <SDL3/SDL_stdinc.h>
 #include <SDL3/SDL_timer.h>
 #include <SDL3/SDL_video.h>
+#include <glm/ext/matrix_transform.hpp> /* TODO */
+#include <glm/glm.hpp>
+#include <glm/gtc/type_ptr.hpp>
 #include <cstdio>
 
 #include "bettola.h"
@@ -31,8 +34,10 @@ Bettola::~Bettola(void) {
 
   SDL_Quit();
 
-  glDeleteVertexArrays(1, &_vao);
-  glDeleteBuffers(1, &_vbo);
+  if(_gl_context) {
+    glDeleteVertexArrays(1, &_vao);
+    glDeleteBuffers(1, &_vbo);
+  }
 }
 
 int Bettola::run(void) {
@@ -46,7 +51,12 @@ int Bettola::run(void) {
     return -1;
   }
 
-  setup_triangle();
+  _projection = glm::ortho(0.0f, 800.0f, 600.0f, 0.0f, -1.0f, 1.0f);
+  _shader.use();
+  unsigned int proj_loc = glGetUniformLocation(_shader.get_id(), "projection");
+  glUniformMatrix4fv(proj_loc, 1, GL_FALSE, glm::value_ptr(_projection));
+
+  setup_quad();
 
   glViewport(0,0,SCREEN_WIDTH, SCREEN_HEIGHT);
 
@@ -95,8 +105,16 @@ void Bettola::render(void) {
   glClear(GL_COLOR_BUFFER_BIT);
 
   _shader.use();
+
+  glm::mat4 model = glm::mat4(1.0f);
+  model = glm::translate(model, glm::vec3(_player.get_x(), _player.get_y(), 0.0f));
+  model = glm::scale(model, glm::vec3(_player.get_width(), _player.get_height(), 1.0f));
+
+  unsigned int model_loc = glGetUniformLocation(_shader.get_id(), "model");
+  glUniformMatrix4fv(model_loc, 1, GL_FALSE, glm::value_ptr(model));
+
   glBindVertexArray(_vao);
-  glDrawArrays(GL_TRIANGLES, 0, 3);
+  glDrawArrays(GL_TRIANGLES, 0, 6);
   glBindVertexArray(0);
 
   SDL_GL_SwapWindow(_window);
@@ -146,12 +164,15 @@ bool Bettola::create_gl_context(void) {
   return true;
 }
 
-void Bettola::setup_triangle(void) {
+void Bettola::setup_quad(void) {
   float vertices[] = {
-    /* Should be a triangle??!?? */
+    /* Should be a quad??!?? */
     -0.5f, -0.5f, 0.0f,
      0.5f, -0.5f, 0.0f,
-    -0.0f,  0.5f, 0.0f,
+     0.5f,  0.5f, 0.0f,
+     0.5f,  0.5f, 0.0f,
+    -0.5f,  0.5f, 0.0f,
+    -0.5f, -0.5f, 0.0f,
   };
 
   glGenVertexArrays(1, &_vao);

src/bettola.h

@@ -1,8 +1,10 @@
 #pragma once
 
 #include <SDL3/SDL.h>
+#include <glm/glm.hpp>
 
 #include "graphics/shader.h"
+#include "game/player.h"
 
 class Bettola {
 public:
@@ -20,7 +22,7 @@ private:
   bool init_glew(void);
   bool create_window(void);
   bool create_gl_context(void);
-  void setup_triangle(void);
+  void setup_quad(void);
 
   bool _is_running;
 
@@ -30,4 +32,7 @@ private:
   Shader _shader;
   unsigned int _vao;
   unsigned int _vbo;
+
+  glm::mat4 _projection;
+  Player _player;
 };

src/game/player.cpp

@@ -7,5 +7,5 @@ Player::Player(void) :
     _height(50.0f) {}
 
 void Player::update(double dt) {
-
+  /* Do some shit? */
 }