remove glfw+gl from forge.c

src/forge.c

@@ -1,5 +1,3 @@
-#include <GLFW/glfw3.h>
-#include <glad/gl.h>
 #include <linmath.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -12,47 +10,30 @@
 
 void error_callback(int error, const char *description) {
   fprintf(stderr, "Error %d: %s\n", error, description);
-  glfwTerminate();
+  close_window(0, true);
   exit(EXIT_FAILURE);
 }
 
 static void key_callback(Window *window, int key,
                          __attribute__((unused)) int scancode, int action,
-                         int mods) {
+                         __attribute__((unused)) int mods) {
   // close window on escape key
-  if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS && mods == 0) {
-    glfwSetWindowShouldClose(window, GLFW_TRUE);
+  if (escape_key(key, action)) {
+    close_window(window, false);
   }
 }
 
 void loop(Window *window, ShaderProgram program) {
-  // TODO remove GLFW references
-  // TODO split into smaller functions
-  int width, height;
-  glfwGetFramebufferSize(window, &width, &height);
-  vec2 resolution = {(float)width, (float)height};
+  Context context;
 
-  glViewport(0, 0, width, height);
-  glClear(GL_COLOR_BUFFER_BIT);
+  context = get_window_context(window);
 
-  mat4x4 m, p, mvp;
-  mat4x4_identity(m);
-  mat4x4_ortho(p, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, 0.0f);
-  mat4x4_mul(mvp, p, m);
+  apply_program(program, context);
 
-  glUseProgram(program.program);
-  glUniformMatrix4fv(program.mvp_location, 1, GL_FALSE, (const GLfloat *)&mvp);
-  glUniform1f(program.itime_location, (const GLfloat)glfwGetTime());
-  glUniform2fv(program.ires_location, 1, (const GLfloat *)&resolution);
-  glBindVertexArray(program.vertex_array);
-  glDrawArrays(GL_TRIANGLES, 0, 6);
-
-  glfwSwapBuffers(window);
-  glfwPollEvents();
+  update_window(window);
 }
 
 void forge_run(Parameters params) {
-  // TODO remove GLFW references
   Window *window;
 
   File fragment_shader = read_file(params.frag_path);
@@ -68,11 +49,11 @@ void forge_run(Parameters params) {
 
   if (program.error) {
     fprintf(stderr, "Failed to compile shaders\n");
-    glfwTerminate();
+    close_window(window, true);
     exit(EXIT_FAILURE);
   }
 
-  while (!glfwWindowShouldClose(window)) {
+  while (!window_should_close(window)) {
     if (params.hot_reload && should_update_file(&fragment_shader)) {
       update_file(&fragment_shader);
       update_program(program, fragment_shader);
@@ -80,7 +61,7 @@ void forge_run(Parameters params) {
     loop(window, program);
   }
 
-  glfwTerminate();
+  close_window(window, true);
 
   free_file(&fragment_shader);
 }

src/shaders.c

@@ -71,4 +71,24 @@ void update_program(ShaderProgram program, File fragment_shader) {
     return;
   }
   glLinkProgram(program.program);
+}
+
+void apply_program(ShaderProgram program, Context context) {
+  mat4x4 m, p, mvp;
+
+  glViewport(0, 0, context.width, context.height);
+  glClear(GL_COLOR_BUFFER_BIT);
+
+  mat4x4_identity(m);
+  mat4x4_ortho(p, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, 0.0f);
+  mat4x4_mul(mvp, p, m);
+
+  vec2 resolution = {(float)context.width, (float)context.height};
+
+  glUseProgram(program.program);
+  glUniformMatrix4fv(program.mvp_location, 1, GL_FALSE, (const GLfloat *)&mvp);
+  glUniform1f(program.itime_location, (const GLfloat)context.time);
+  glUniform2fv(program.ires_location, 1, (const GLfloat *)&resolution);
+  glBindVertexArray(program.vertex_array);
+  glDrawArrays(GL_TRIANGLES, 0, 6);
 }

src/shaders.h

@@ -7,4 +7,6 @@ ShaderProgram init_program(File fragment_shader);
 
 void update_program(ShaderProgram program, File fragment_shader);
 
+void apply_program(ShaderProgram program, Context context);
+
 #endif

src/types.h

@@ -46,4 +46,10 @@ typedef struct ShaderProgram {
 
 typedef GLFWwindow Window;
 
+typedef struct Context {
+  int width;
+  int height;
+  double time;
+} Context;
+
 #endif

src/window.c

@@ -1,5 +1,6 @@
 #include <GLFW/glfw3.h>
 #include <linmath.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -92,4 +93,37 @@ Window *init_window(Parameters params,
   use_window(window);
 
   return window;
+}
+
+void update_window(Window *window) {
+  // swap front and back buffers
+  glfwSwapBuffers(window);
+  // listen to mouse and keyboard events
+  glfwPollEvents();
+}
+
+Context get_window_context(Window *window) {
+  Context context;
+
+  glfwGetFramebufferSize(window, &context.width, &context.height);
+
+  context.time = glfwGetTime();
+
+  return context;
+}
+
+void close_window(Window *window, bool hard) {
+  if (hard) {
+    glfwTerminate();
+  } else {
+    glfwSetWindowShouldClose(window, GLFW_TRUE);
+  }
+}
+
+bool window_should_close(Window *window) {
+  return glfwWindowShouldClose(window) == GLFW_TRUE;
+}
+
+bool escape_key(int key, int action) {
+  return key == GLFW_KEY_ESCAPE && action == GLFW_PRESS;
 }

src/window.h

@@ -7,4 +7,14 @@ Window *init_window(Parameters params,
                     void (*error_callback)(int, const char *),
                     void (*key_callback)(Window *, int, int, int, int));
 
+void update_window(Window *window);
+
+Context get_window_context(Window *window);
+
+void close_window(Window *window, bool hard);
+
+bool window_should_close(Window *window);
+
+bool escape_key(int key, int action);
+
 #endif