add overridable update() and draw() callbacks

6 files changed, 141 insertions, 80 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8bf34bb..c78eafa 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,7 +9,7 @@ add_executable(honey_engine_demo demo.c)
 
 set(CMAKE_C_FLAGS "-g")
 
-add_library(honey src/honey_setup.c src/texture.c src/shader.c src/mesh.c)
+add_library(honey src/honey.c src/texture.c src/shader.c src/mesh.c)
 add_library(glad src/glad.c)
 add_library(stb_image src/stb_image.c)
 
diff --git a/demo.c b/demo.c
index 08c11fb..94fdd66 100644
--- a/demo.c
+++ b/demo.c
@@ -1,5 +1,7 @@
 #include "include/honey.h"
 
+honey_window window;
+
 unsigned int screen_width = 640;
 unsigned int screen_height = 480;
 
@@ -13,6 +15,13 @@ float cameraPitch = 0;
 float cameraYaw = 0;
 const float cameraMouseSensitivity = 0.1;
 
+honey_mesh cube;
+honey_shader shader;
+honey_texture container;
+honey_texture happy_face;
+
+mat4 model, view, projection;
+
 bool wireframe = false;
 bool fKeyDown = false;
 
@@ -56,7 +65,11 @@ void mouseCallback(GLFWwindow* window, double x, double y) {
 
 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
 
-void processInput(GLFWwindow* window, float dt) {
+void update(float dt) {
+  glfwPollEvents();
+
+  glm_rotate_x(model, glm_rad(10*dt), model);
+  
   if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS) {
     glfwSetWindowShouldClose(window, true);
   }
@@ -96,27 +109,57 @@ void processInput(GLFWwindow* window, float dt) {
   }
 }
 
-/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+void draw() {
+  glClearColor(0.4f, 0.4f, 0.4f, 1.0);
+  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+  if (wireframe) {
+    glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+  }
+  else {
+    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+  }
+
+  glm_perspective_default(((float)screen_width)/screen_height, projection);
+  honey_shader_set_matrix_4fv(shader, "projection", (float*) projection);
+
+  vec3 cameraDirection;
+  glm_vec3_add(cameraPosition, cameraFacing, cameraDirection);
+  glm_lookat(cameraPosition, cameraDirection, cameraUp, view);
+  honey_shader_set_matrix_4fv(shader, "view", (float*) view);
+    
+  honey_shader_set_matrix_4fv(shader, "model", (float*) model);
+    
+  glActiveTexture(GL_TEXTURE0);
+  glBindTexture(GL_TEXTURE_2D, container.texture_id);
+  glActiveTexture(GL_TEXTURE1);
+  glBindTexture(GL_TEXTURE_2D, happy_face.texture_id);
+
+  honey_mesh_draw(cube, shader);
+    
+  glfwSwapBuffers(window);
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
 
 int main() {
-  honey_window window = honey_setup(screen_width, screen_height, "hello, world!");
+  window = honey_setup(screen_width, screen_height, "hello, world!");
 
   honey_set_resize_callback(window, framebufferResizeCallback);
   honey_set_mouse_move_callback(window, mouseCallback);
 
-  /* load box texture */
-  honey_texture box;
-  if (honey_texture_new(&box, "container.jpg", false) != TEXTURE_OK) {
+  /* load container texture */
+  if (honey_texture_new(&container, "container.jpg", false) != TEXTURE_OK) {
     return 1;
   }
 
   /* load happy face texture */
-  honey_texture happy_face;
   if (honey_texture_new(&happy_face, "happy.png", true) != TEXTURE_OK) {
     return 1;
   }
   
-  honey_shader shader;
   if (honey_shader_load(&shader, "demo.vs", "demo.fs") != SHADER_OK) {
     return 1;
   }
@@ -146,7 +189,6 @@ int main() {
                              0, 1, 4,
                              1, 4, 5 };
 
-  honey_mesh cube;
   unsigned int attribute_sizes[] = { 3, 3, 2 }; /* position, color, texture coordinate */
   enum honey_mesh_result result = honey_mesh_new(&cube,
                                                  vertices, 8, 3, attribute_sizes,
@@ -160,7 +202,6 @@ int main() {
   honey_shader_set_int(shader, "boxTexture", 0);
   honey_shader_set_int(shader, "happyTexture", 1);
 
-  mat4 model, view, projection;
   glm_mat4_identity(model);
   glm_rotate_x(model, glm_rad(-55), model);
   honey_shader_set_matrix_4fv(shader, "model", (float*) model);
@@ -177,48 +218,10 @@ int main() {
 
   /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
 
-  float prevTime = 0;
-  float currentTime = 0;
-  float dt = 0;
+  honey_set_update_callback(&update);
+  honey_set_draw_callback(&draw);
 
-  while(!glfwWindowShouldClose(window)) {
-    currentTime = (float) glfwGetTime();
-    dt = currentTime - prevTime;
-    prevTime = currentTime;
-
-    processInput(window, dt);
-
-    glClearColor(0.4f, 0.4f, 0.4f, 1.0);
-    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
-    if (wireframe) {
-      glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
-    }
-    else {
-      glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
-    }
-
-    glm_perspective_default(((float)screen_width)/screen_height, projection);
-    honey_shader_set_matrix_4fv(shader, "projection", (float*) projection);
-
-    vec3 cameraDirection;
-    glm_vec3_add(cameraPosition, cameraFacing, cameraDirection);
-    glm_lookat(cameraPosition, cameraDirection, cameraUp, view);
-    honey_shader_set_matrix_4fv(shader, "view", (float*) view);
-    
-    glm_rotate_x(model, glm_rad(10*dt), model);
-    honey_shader_set_matrix_4fv(shader, "model", (float*) model);
-    
-    glActiveTexture(GL_TEXTURE0);
-    glBindTexture(GL_TEXTURE_2D, box.texture_id);
-    glActiveTexture(GL_TEXTURE1);
-    glBindTexture(GL_TEXTURE_2D, happy_face.texture_id);
-
-    honey_mesh_draw(cube, shader);
-    
-    glfwSwapBuffers(window);
-    glfwPollEvents();
-  }
+  honey_run(window);
 
   honey_mesh_delete(cube);
   honey_shader_delete(shader);
diff --git a/include/honey.h b/include/honey.h
index 9b048c0..7ae7789 100644
--- a/include/honey.h
+++ b/include/honey.h
@@ -1,6 +1,7 @@
 #ifndef HONEY_ENGINE_H
 #define HONEY_ENGINE_H
 
+/** @file Defines the basic loading and callback functions. */
 #include "common.h"
 #include "mesh.h"
 #include "shader.h"
@@ -8,8 +9,24 @@
 
 typedef GLFWwindow* honey_window;
 
+/** @brief Initialize Honey.
+ *
+ * @param[in] screen_width The desired width of the screen in pixels
+ * @param[in] screen_height The desired height of the screen in pixels
+ * @param[in] window_title Title to use for the window.
+ */
 honey_window honey_setup(int screen_width, int screen_height, char* window_title);
 
+static void (*honey_update_callback)(float dt);
+static void (*honey_draw_callback)();
+static float honey_draw_dt = 0.16;
+
+void honey_set_update_callback(void (*update_callback)(float));
+void honey_set_draw_callback(void (*draw_callback)());
+void honey_set_fps(unsigned int);
+
+void honey_run(honey_window window);
+
 #define honey_set_resize_callback glfwSetFramebufferSizeCallback
 #define honey_set_mouse_move_callback glfwSetCursorPosCallback
 
diff --git a/src/honey.c b/src/honey.c
new file mode 100644
index 0000000..c55ddc2
--- /dev/null
+++ b/src/honey.c
@@ -0,0 +1,66 @@
+#include "include/honey.h"
+
+static void default_honey_update_callback(float dt) {}
+static void default_honey_draw_callback() {}
+
+honey_window honey_setup(int screen_width, int screen_height, char* window_title) {
+  honey_update_callback = &default_honey_update_callback;
+  honey_draw_callback = &default_honey_draw_callback;
+  
+  glfwInit();
+  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+  glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
+
+  honey_window window = glfwCreateWindow(screen_width, screen_height, window_title, NULL, NULL);
+  if (window == NULL) {
+    fprintf(stderr, "ERROR: failed to create window!\n");
+    glfwTerminate();
+    return NULL;
+  }
+
+  glfwMakeContextCurrent(window);
+  glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
+
+  if (!gladLoadGLLoader((GLADloadproc) glfwGetProcAddress)) {
+    fprintf(stderr, "ERROR: failed to initialize GLAD!\n");
+    glfwTerminate();
+    return NULL;
+  }
+
+  return window;
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+void honey_set_update_callback(void (*update_callback)(float)) {
+  honey_update_callback = update_callback;
+}
+
+void honey_set_draw_callback(void (*draw_callback)()) {
+  honey_draw_callback = draw_callback;
+}
+
+void honey_set_fps(unsigned int fps) {
+  honey_draw_dt = 1.0f / fps;
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+void honey_run(honey_window window) {
+  float prevTime = 0;
+  float currentTime = 0;
+  float dt;
+  float draw_dt = 0;
+
+  while(!glfwWindowShouldClose(window)) {
+    currentTime = (float) glfwGetTime();
+    dt = currentTime - prevTime;
+    prevTime = currentTime;
+
+    honey_update_callback(dt);
+    honey_draw_callback();
+  }
+}
+    
+  
diff --git a/src/honey_setup.c b/src/honey_setup.c
deleted file mode 100644
index 247c325..0000000
--- a/src/honey_setup.c
+++ /dev/null
@@ -1,28 +0,0 @@
-#include "include/honey.h"
-
-honey_window honey_setup(int screen_width, int screen_height, char* window_title) {
-  glfwInit();
-  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-  glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
-
-  honey_window window = glfwCreateWindow(screen_width, screen_height, window_title, NULL, NULL);
-  if (window == NULL) {
-    fprintf(stderr, "ERROR: failed to create window!\n");
-    glfwTerminate();
-    return NULL;
-  }
-
-  glfwMakeContextCurrent(window);
-  glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
-
-  if (!gladLoadGLLoader((GLADloadproc) glfwGetProcAddress)) {
-    fprintf(stderr, "ERROR: failed to initialize GLAD!\n");
-    glfwTerminate();
-    return NULL;
-  }
-
-  return window;
-}
-
-  
diff --git a/src/run_callbacks.c b/src/run_callbacks.c
new file mode 100644
index 0000000..f6b1379
--- /dev/null
+++ b/src/run_callbacks.c
@@ -0,0 +1,3 @@
+#include "honey.h"
+
+