feat: factor out game code

Makefile

@@ -1,6 +1,6 @@
 CFLAGS := -Wall -Wextra
 LDFLAGS = -lglfw -lm -lGL -I./glad/include
 
-domino-dungeon: main.c glad/src/glad.c
+domino-dungeon: main.c game.c game.h glad/src/glad.c
 	$(CC) ${CFLAGS} ${LDFLAGS} -o $@ $^
 

game.c

@@ -0,0 +1,25 @@
+
+#include <stdio.h>
+#include <glad/glad.h>
+#include <GLFW/glfw3.h>
+#include <math.h>
+
+#include "game.h"
+
+void character_callback(GLFWwindow* window, unsigned int codepoint) {
+  printf("%c\n", codepoint);
+}
+
+void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods) {
+  if (action != GLFW_PRESS) return;
+  switch (key) {
+    case GLFW_KEY_ENTER:
+      break;
+    case GLFW_KEY_BACKSPACE:
+      break;
+  }
+}
+
+void draw_image(decoded_image img) {
+  for (int i = 0; i < img.buf_size; i++) img.buf[i] = i;
+}

game.h

@@ -0,0 +1,10 @@
+
+#include <stddef.h>
+#include <stdint.h>
+
+typedef struct decoded_image {
+  size_t width;
+  size_t height;
+  uint32_t *buf;
+  size_t buf_size;
+} decoded_image;

main.c

@@ -4,16 +4,16 @@
 #include <glad/glad.h>
 #include <GLFW/glfw3.h>
 #include <math.h>
+#include <stdlib.h>
+
+#include "game.h"
 
 unsigned int SCR_WIDTH = 800;
 unsigned int SCR_HEIGHT = 600;
 
-typedef struct decoded_image {
-  size_t width;
-  size_t height;
-  uint32_t *buf;
-  ssize_t buf_size;
-} decoded_image;
+extern void character_callback(GLFWwindow* window, unsigned int codepoint);
+extern void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods);
+extern void draw_image(decoded_image img);
 
 struct decoded_image canvas = {
   .width = 256,
@@ -63,7 +63,6 @@ const uint32_t COLOR_RGBA = 0xFF21FF00;
 int main(int argc, const char *argv[]) {
 
   canvas.buf = malloc(canvas.buf_size * sizeof(int));
-  for (int i = 0; i < canvas.buf_size; i++) canvas.buf[i] = i;
 
   glfwInit();
   glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
@@ -180,6 +179,8 @@ int main(int argc, const char *argv[]) {
     glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
     glClear(GL_COLOR_BUFFER_BIT);
 
+    draw_image(canvas);
+
     // bind textures on corresponding texture units
     glActiveTexture(GL_TEXTURE);
     glBindTexture(GL_TEXTURE_2D, texture);