slider widget, tons of fixes and improvements for win32, reworked font loading.

include/pgpl/gui/helpers.h

@@ -7,6 +7,13 @@
 extern "C" {
 #endif
 
+/* This function adjusts the values of the parameters that are passed to the
+ * event method to match the values that are passed to the render function. */
+void pgpl_gui_widget_adjust_event_params(PGPL_GuiWidget *widget,
+                                         PGPL_GuiTheme *theme, double *x,
+                                         double *y, double *max_width,
+                                         double *max_height);
+
 /* This function basically subtracts margin, border and padding from the
  * max_width and max_height, and then return that through the width and height
  * pointers. */
@@ -31,6 +38,11 @@ void pgpl_gui_widget_render_full(PGPL_GuiWidget *widget,
                                  double x, double y, double max_width,
                                  double max_height);
 
+/* Checks if a point is within the bounds of the area. */
+bool pgpl_gui_widget_within_area(double x, double y, double area_x,
+                                 double area_y, double area_width,
+                                 double area_height);
+
 /* Checks if x and y lie within the visible bounds of a widget, accounting for
  * margin, border and padding and returns true or false. */
 bool pgpl_gui_widget_within_bounds(PGPL_GuiWidget *widget, PGPL_GuiTheme *theme,

include/pgpl/gui/widgets.h

@@ -89,6 +89,30 @@ PGPL_GuiWidget *pgpl_gui_empty_widget_create(void);
 /* Destroys a empty widget. */
 void pgpl_gui_empty_widget_destroy(PGPL_GuiWidget *empty_widget);
 
+/* This is the struct for a slider widget. The inversed option inverses its
+ * slide direction, vertical determines if it's vertical or horizontal. The
+ * bar_height is the height of the slider bar. The slide_callback gets called
+ * whenever there is sliding activity. */
+typedef struct PGPL_GuiSliderWidget {
+  PGPL_GuiWidget parent;
+  uint32_t bar_height;
+  bool inversed;
+  bool vertical;
+  double current_value;
+  void (*slide_callback)(void *app_data, double value);
+  /* Do not modify the following two attributes manually. */
+  bool sliding;
+  double last_pos;
+} PGPL_GuiSliderWidget;
+
+/* This creates a new slider with the given properties. */
+PGPL_GuiSliderWidget *pgpl_gui_slider_widget_create(
+    uint32_t bar_height, bool inversed, bool vertical, double value,
+    void (*slide_callback)(void *app_data, double value));
+
+/* This destorys a slider widget. */
+void pgpl_gui_slider_widget_destroy(PGPL_GuiSliderWidget *slider_widget);
+
 #ifdef __cplusplus
 }
 #endif

include/pgpl/log.h

@@ -7,17 +7,24 @@
 extern "C" {
 #endif
 
+/* These are the different supported logging levels. */
 typedef enum PGPL_LogLevel {
-  PGPL_LOG_LEVEL_DEBUG,
-  PGPL_LOG_LEVEL_INFO,
-  PGPL_LOG_LEVEL_WARN,
-  PGPL_LOG_LEVEL_ERROR,
+  PGPL_LOG_LEVEL_DEBUG, /* For frequent debug prints, use this. */
+  PGPL_LOG_LEVEL_INFO,  /* For general info, that isn't spammed. */
+  PGPL_LOG_LEVEL_WARN,  /* For non-critical problems. */
+  PGPL_LOG_LEVEL_ERROR, /* For critical problems that could halt the program */
 } PGPL_LogLevel;
 
+/* This sets the minimum level required for a message to be displayed. */
 void pgpl_log_set_minimum_level(PGPL_LogLevel level);
 
+/* This selects the file that things should be outputted to. By default this is
+ * goes to stderr. */
 void pgpl_log_output_file(FILE *file);
 
+/* This logs a message. This function can be used like printf. The output
+ * follows the following scheme: [ERROR] <message>
+ * It is also terminated by a newline. */
 void pgpl_log_message(PGPL_LogLevel level, const char *message, ...);
 
 #ifdef __cplusplus

include/pgpl/window/thread.h

@@ -14,8 +14,9 @@ extern "C" {
  * can be any custom pointer to anything that might be needed inside of the
  * event_loop. If the user_data is not needed it can also be NULL.
  *
- * Returning false from the event_loop will close the window.
- */
+ * Returning false from the event_loop will close the window. Do not call any of
+ * the window_thread functions from within the event loop, as this will cause
+ * the thread to lock up. Use the window functions directly. */
 PGPL_WindowThread *pgpl_window_thread_create(
     const char *title, uint32_t width, uint32_t height, int32_t x, int32_t y,
     bool (*event_loop)(PGPL_Window *window, PGPL_WindowEventType event,
@@ -93,8 +94,7 @@ void pgpl_window_thread_reparent_to(PGPL_WindowThread *window_thread,
  * pgpl_window_get_raw_window for more information. */
 void *pgpl_window_thread_get_raw_window(PGPL_WindowThread *window_thread);
 
-/* This function halts until the window_thread is destroyed. This function only
- * works once per window_thread. */
+/* This function halts until the window_thread is destroyed. */
 void pgpl_window_thread_await_destruction(PGPL_WindowThread *window_thread);
 
 #ifdef __cplusplus