07: Extend and play around with batching

07-boilerplate/README.md

@@ -1,3 +1,8 @@
-# Boilerplate API
+<p align="center"> 
+    <img src=".imgs/showcase.png" width="300" /> 
+</p>
 
-Creating a boilerplate API to abstract away OpenGL
+# Boilerplate
+
+Creating a boilerplate API to abstract away OpenGL. 
+ - Also added my first ever batch renderer 

07-boilerplate/assets/shaders/default_vertex.glsl

@@ -15,8 +15,9 @@ out float _ctt;
 
 void main() {
     vec3 origined_position = origin.xyz + position.xyz;
+    origined_position *= 0.2;
     //gl_Position = projection_matrix * view_matrix * position;
-    gl_Position = projection_matrix * view_matrix * vec4(position.xyz, 1.0);
+    gl_Position = projection_matrix * view_matrix * vec4(origined_position, 1.0);
     _color = color;
     _texture_position = texture_position;
     _ctt = ctt;

07-boilerplate/src/base/graphics/graphics.hpp

@@ -7,4 +7,4 @@
 #define DEFAULT_CTT_ATTRIBUTE       4 
 
 #define QUAD                        6 
-#define DEFAULT_VBO_SIZE            QUAD * 1000 // unit: rows of RenderData
+#define DEFAULT_VBO_SIZE            QUAD * 1000000 // unit: rows of RenderData

07-boilerplate/src/base/graphics/renderer.cpp

@@ -92,7 +92,7 @@ int Renderer::setup(std::optional<Program> program) {
     glEnableVertexAttribArray(DEFAULT_TEXTURE_ATTRIBUTE);
 
     glVertexAttribPointer(
-        DEFAULT_COLOR_ATTRIBUTE, 
+        DEFAULT_CTT_ATTRIBUTE, 
         1, 
         GL_FLOAT,
         GL_FALSE,
@@ -107,16 +107,29 @@ int Renderer::setup(std::optional<Program> program) {
     return RET_OK;
 }
 
-void Renderer::render() {
+void Renderer::draw(struct RendererData data) {
+    if (batch_buffer.size() >= DEFAULT_VBO_SIZE) {
+        LOG(LOG_WARN, "Batch buffer limit reached!");
+        return;
+    }
+
+    batch_buffer.push_back(data);
+}
+
+void Renderer::batch() {
     glBindVertexArray(this->array_buffer_id);
     glBindBuffer(GL_ARRAY_BUFFER, this->vertex_buffer_id);
 
+    glBufferSubData(GL_ARRAY_BUFFER, 0, batch_buffer.size() * sizeof(struct RendererData), batch_buffer.data());
+
     glUseProgram(this->program.id);
 
     glUniformMatrix4fv(glGetUniformLocation(this->program.id, "view_matrix"), 1, GL_FALSE, &this->view_matrix[0][0]);
     glUniformMatrix4fv(glGetUniformLocation(this->program.id, "projection_matrix"), 1, GL_FALSE, &this->projection_matrix[0][0]);
 
     glDrawArrays(GL_TRIANGLES, 0, DEFAULT_VBO_SIZE);
+
+    batch_buffer.clear();
 }
 
 void Renderer::logic() {

07-boilerplate/src/base/graphics/renderer.hpp

@@ -24,5 +24,9 @@ public:
 
     int setup(std::optional<Program> program = std::nullopt);
     void logic();
-    void render();
+
+    std::vector<struct RendererData> batch_buffer;
+
+    void draw(struct RendererData data);
+    void batch();
 };

07-boilerplate/src/main.cpp

@@ -1,5 +1,6 @@
 #include <iostream>
 #include <fstream>
+#include <cstdlib>
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
 #include <stb/stb_image.h>
@@ -22,19 +23,56 @@ int main() {
         return RET_ERR;
     }
 
-    Sprite new_sprite(main_renderer.vertex_buffer_id);
-    new_sprite.bake();
+    std::vector<Sprite> sprites;
 
-    new_sprite.origin = glm::vec4(0.0f, 0.0f, 0.0f, 1.0f);
-    new_sprite.color = glm::vec4(1.0f, 0.0f, 0.0f, 1.0f);
+    int limit_x = 10; 
+    int limit_y = 10;
+    float scale = 0.2;
 
+    for (int i = -limit_x/2; i < limit_x/2; i++) {
+        for (int j = -limit_y/2; j < limit_y/2; j++) {
+            Sprite new_sprite(main_renderer);
+            new_sprite.bake();
+
+            float r = (float) rand() / (float) RAND_MAX; 
+            float g = (float) rand() / (float) RAND_MAX; 
+            float b = (float) rand() / (float) RAND_MAX; 
+
+            new_sprite.color = glm::vec4(r, g, b, 1.0f);
+            new_sprite.origin = glm::vec4(i*scale, j*scale, 0.0f, 0.0f);
+
+            sprites.push_back(new_sprite);
+        }
+    } 
+    
     while (!glfwWindowShouldClose(window.window)) {
         glClearColor(0, 0, 0, 1);
         glClear(GL_COLOR_BUFFER_BIT);
 
-        new_sprite.update();
+        for (int i = 0; i < sprites.size(); i++) {
+            // randomly update their position by little 
+            float x = ((float) rand() / (float) RAND_MAX) * 0.5;
+            float y = ((float) rand() / (float) RAND_MAX) * 0.5;
+
+            int x_side = rand() % 2;
+            int y_side = rand() % 2;
+
+            if (x_side == 0)
+                sprites[i].origin.x += x; 
+            else 
+                sprites[i].origin.x -= x; 
+
+            if (y_side == 0) 
+                sprites[i].origin.y += y; 
+            else 
+                sprites[i].origin.y -= y;
+
+
+            sprites[i].update();
+        }
+
         main_renderer.logic();
-        main_renderer.render();
+        main_renderer.batch();
 
         glfwPollEvents();
         glfwSwapBuffers(window.window);

07-boilerplate/src/sprites/sprite.cpp

@@ -3,19 +3,19 @@
 #include <glm/vec4.hpp>
 #include <glm/vec2.hpp>
 #include <GL/glew.h>
-#include "../base/graphics/renderer_pack.hpp"
+#include "../base/graphics/renderer.hpp"
 #include "sprite.hpp"
 
-Sprite::Sprite(GLuint vertex_buffer_id) {
+Sprite::Sprite(Renderer &renderer) : renderer(renderer) {
     this->vertices = std::vector<glm::vec4>();
     this->origin = glm::vec4(1.0f);
-    this->color = glm::vec4(1.0f);
+    this->color = glm::vec4(1.0f, 1.0f, 1.0f, 1.0f);
     this->texture_position = glm::vec2(0.0f);
     this->ctt = 1.0f;
-    this->vertex_buffer_id = vertex_buffer_id;
 }
 
-void Sprite::bake() {
+// prepare data
+void Sprite::bake() { 
     this->vertices.push_back(glm::vec4(0.5f, 0.5f, 0.0f, 0.0f));
     this->vertices.push_back(glm::vec4(0.5f, -0.5f, 0.0f, 0.0f));
     this->vertices.push_back(glm::vec4(-0.5f, -0.5f, 0.0f, 0.0f));
@@ -35,9 +35,7 @@ void Sprite::update() {
             .ctt_ratio = this->ctt
         }; 
 
-        glBindBuffer(GL_ARRAY_BUFFER, this->vertex_buffer_id);
-        glBufferSubData(GL_ARRAY_BUFFER, i*sizeof(struct RendererData), sizeof(struct RendererData), &data);
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        this->renderer.draw(data);
     }
 }
 

07-boilerplate/src/sprites/sprite.hpp

@@ -5,6 +5,7 @@
 #include <glm/vec4.hpp>
 #include <glm/vec2.hpp>
 #include <GL/glew.h>
+#include "../base/graphics/renderer.hpp"
 
 class Sprite {
 public:
@@ -14,9 +15,10 @@ public:
     glm::vec2 texture_position;
     float ctt;
 
-    GLuint vertex_buffer_id;
+    // GLuint vertex_buffer_id;
+    Renderer &renderer;
 
-    Sprite(GLuint vertex_buffer_id);
+    Sprite(Renderer &renderer);
     ~Sprite();
 
     void bake();