/* Auxiliary functions for making simple OpenGL programs */
/* Kevin Perry  ICGL  Sep 1995 */
#ifndef __PGL_H__
#define __PGL_H__

/***********************************************
 *    HERE IS AN EXAMPLE USAGE OF THIS MODULE:
 *	(opens a 400x400 pixel window, and paints it black)
 *
 * #include <pgl.h>
 *
 * String config[] = { "*geometry: =400x400", NULL };
 * 
 * static void draw_me(int winid, pglCallbackInfo info)
 * {
 *	glClearIndex(0);
 *	glClear(GL_COLOR_BUFFER_BIT);
 * }
 * 
 * main(int argc, char** argv)
 * {
 * 	pglInitialize("Sample", config, PGL_INDEX);
 * 	pglOpenWindow(argv[0], draw_me);
 * 	pglMainLoop();
 * }
 * 
************************************************/

#include <X11/Intrinsic.h>
#include <Xm/Xm.h>
#include <GL/GLwMDrawA.h>

#ifdef __cplusplus
extern "C" {
#endif

/* callback reasons: GraphicsInitialization, WindowExposure (redraw),
 *    WindowResize, and InputEventReceived
 */
#define PGL_GINIT	GLwCR_GINIT
#define PGL_EXPOSE	GLwCR_EXPOSE
#define PGL_RESIZE	GLwCR_RESIZE
#define PGL_INPUT	GLwCR_INPUT
#define PGL_TIMEOUT	42
#define PGL_IDLE	43	/* idle-callbacks are not called if you use pglHandleEvents() */

/* typedefs for callback routines
*/
typedef struct _pglCallbackInfo { /* (looks like a GLwDrawingAreaCallbackStruct) */
	int		reason;
	XEvent*		event;
	Dimension	width;
	Dimension	height;
} *pglCallbackInfo;

typedef void pglCallback(int winid, pglCallbackInfo info);

/* flags for pglOpenWindow()
*/
#define PGL_DOUBLE	0x01
#define PGL_RGBA	0x02
/* flags meaning "not"-something-from-above... */
#define PGL_SINGLE	0x00
#define PGL_INDEX	0x00

/**********************************/
/* EXTERNAL FUNCTION DECLARATIONS */
/**********************************/

/* window creation */
Widget	pglInitialize(char* appClassName, char** resources); 
int	pglOpenWindow(char* title, pglCallback initFunc, int flags);
int	pglOpenSubwindow(Widget parent, char* name,
			pglCallback initRoutine, int flags);

/* program control routines */
void	pglMainLoop(void);
void	pglHandleEvents(void);

/* misc. window operations */
void	pglSetCallback(int winid, int reason, pglCallback func);
void	pglSetCurrentWindow(int winid);
void	pglSwapBuffers(int winid);
void	pglSetColors(int winid, int num, float*rgb);
void	pglSetTimeout(int winid, float seconds);

/* menu operations */
void	pglMakeMenu(int winid, char* title);
void	pglAddMenuItem(int winid, char* item, int value,
			void (*cb)(Widget, XtPointer, XtPointer));

/* window activation */
void	pglManageWindows(void);
void	pglManageWindow(int winid);
void	pglUnmanageWindow(int winid);

/* "get" functions for X and GL objects (usually unneeded) */
XtAppContext	pglGetAppContext(void);
Widget		pglGetAppWidget(void);
GLXContext	pglGetGLContext(int winid);
Widget		pglGetGLWidget(int winid);
Widget		pglGetShell(int winid);

/* text string handling utility funcitons */
GLuint		pglMakeFont(char*);
void		pglDrawString(char*, GLuint);

#ifdef __cplusplus
}
#endif

#endif