xmesap.h

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

   PIXEL = xmesa->xm_visual->RtoPixel[(R)+d]			\
         | xmesa->xm_visual->GtoPixel[(G)+d]			\
         | xmesa->xm_visual->BtoPixel[(B)+d];			\
}



/**
 * If pixelformat==PF_8A8B8G8R:
 */
#define PACK_8A8B8G8R( R, G, B, A )	\
	( ((A) << 24) | ((B) << 16) | ((G) << 8) | (R) )


/**
 * Like PACK_8A8B8G8R() but don't use alpha.  This is usually an acceptable
 * shortcut.
 */
#define PACK_8B8G8R( R, G, B )   ( ((B) << 16) | ((G) << 8) | (R) )



/**
 * If pixelformat==PF_8R8G8B:
 */
#define PACK_8R8G8B( R, G, B)	 ( ((R) << 16) | ((G) << 8) | (B) )


/**
 * If pixelformat==PF_5R6G5B:
 */
#define PACK_5R6G5B( R, G, B)	 ( (((R) & 0xf8) << 8) | (((G) & 0xfc) << 3) | ((B) >> 3) )


/**
 * If pixelformat==PF_8A8R8G8B:
 */
#define PACK_8A8R8G8B( R, G, B, A )	\
	( ((A) << 24) | ((R) << 16) | ((G) << 8) | (B) )



/**
 * If pixelformat==PF_DITHER:
 *
 * Improved 8-bit RGB dithering code contributed by Bob Mercier
 * ([e-mail]).  Thanks Bob!
 */
#ifdef DITHER666
# define DITH_R   6
# define DITH_G   6
# define DITH_B   6
# define DITH_MIX(r,g,b)  (((r) * DITH_G + (g)) * DITH_B + (b))
#else
# define DITH_R	5
# define DITH_G	9
# define DITH_B	5
# define DITH_MIX(r,g,b)  (((g) << 6) | ((b) << 3) | (r))
#endif
#define DITH_DX	4
#define DITH_DY	4
#define DITH_N	(DITH_DX * DITH_DY)

#define _dither(C, c, d)   (((unsigned)((DITH_N * (C - 1) + 1) * c + d)) >> 12)

#define MAXC	256
extern const int xmesa_kernel8[DITH_DY * DITH_DX];

/* Dither for random X,Y */
#define DITHER_SETUP						\
	int __d;						\
	unsigned long *ctable = XMESA_BUFFER(ctx->DrawBuffer)->color_table;

#define DITHER( X, Y, R, G, B )				\
	(__d = xmesa_kernel8[(((Y)&3)<<2) | ((X)&3)],	\
	 ctable[DITH_MIX(_dither(DITH_R, (R), __d),	\
		         _dither(DITH_G, (G), __d),	\
		         _dither(DITH_B, (B), __d))])

/* Dither for random X, fixed Y */
#define XDITHER_SETUP(Y)					\
	int __d;						\
	unsigned long *ctable = XMESA_BUFFER(ctx->DrawBuffer)->color_table;	\
	const int *kernel = &xmesa_kernel8[ ((Y)&3) << 2 ];

#define XDITHER( X, R, G, B )				\
	(__d = kernel[(X)&3],				\
	ctable[DITH_MIX(_dither(DITH_R, (R), __d),	\
		        _dither(DITH_G, (G), __d),	\
		        _dither(DITH_B, (B), __d))])



/*
 * Dithering for flat-shaded triangles.  Precompute all 16 possible
 * pixel values given the triangle's RGB color.  Contributed by Martin Shenk.
 */
#define FLAT_DITHER_SETUP( R, G, B )					\
	GLushort ditherValues[16];					\
	{								\
	   unsigned long *ctable = XMESA_BUFFER(ctx->DrawBuffer)->color_table;	\
	   int msdr = (DITH_N*((DITH_R)-1)+1) * (R);			\
	   int msdg = (DITH_N*((DITH_G)-1)+1) * (G);			\
	   int msdb = (DITH_N*((DITH_B)-1)+1) * (B);			\
	   int i;							\
	   for (i=0;i<16;i++) {						\
	      int k = xmesa_kernel8[i];					\
	      int j = DITH_MIX( (msdr+k)>>12, (msdg+k)>>12, (msdb+k)>>12 );\
	      ditherValues[i] = (GLushort) ctable[j];			\
	   }								\
        }

#define FLAT_DITHER_ROW_SETUP(Y)					\
	GLushort *ditherRow = ditherValues + ( ((Y)&3) << 2);

#define FLAT_DITHER(X)  ditherRow[(X)&3]



/**
 * If pixelformat==PF_LOOKUP:
 */
#define _dither_lookup(C, c)   (((unsigned)((DITH_N * (C - 1) + 1) * c)) >> 12)

#define LOOKUP_SETUP						\
	unsigned long *ctable = XMESA_BUFFER(ctx->DrawBuffer)->color_table

#define LOOKUP( R, G, B )				\
	ctable[DITH_MIX(_dither_lookup(DITH_R, (R)),	\
		        _dither_lookup(DITH_G, (G)),	\
		        _dither_lookup(DITH_B, (B)))]


/**
 * If pixelformat==PF_HPCR:
 *
 *      HP Color Recovery dithering               ([e-mail] 30/08/95)
 *      HP has on it's 8-bit 700-series computers, a feature called
 *      'Color Recovery'.  This allows near 24-bit output (so they say).
 *      It is enabled by selecting the 8-bit  TrueColor  visual AND
 *      corresponding  colormap (see tkInitWindow) AND doing some special
 *      dither.
 */
extern const short xmesa_HPCR_DRGB[3][2][16];

#define DITHER_HPCR( X, Y, R, G, B )					   \
  ( ((xmesa->xm_visual->hpcr_rgbTbl[0][R] + xmesa_HPCR_DRGB[0][(Y)&1][(X)&15]) & 0xE0)     \
  |(((xmesa->xm_visual->hpcr_rgbTbl[1][G] + xmesa_HPCR_DRGB[1][(Y)&1][(X)&15]) & 0xE0)>>3) \
  | ((xmesa->xm_visual->hpcr_rgbTbl[2][B] + xmesa_HPCR_DRGB[2][(Y)&1][(X)&15])>>6)	   \
  )



/**
 * If pixelformat==PF_1BIT:
 */
extern const int xmesa_kernel1[16];

#define SETUP_1BIT  int bitFlip = xmesa->xm_visual->bitFlip
#define DITHER_1BIT( X, Y, R, G, B )	\
	(( ((int)(R)+(int)(G)+(int)(B)) > xmesa_kernel1[(((Y)&3) << 2) | ((X)&3)] ) ^ bitFlip)



/**
 * If pixelformat==PF_GRAYSCALE:
 */
#define GRAY_RGB( R, G, B )   XMESA_BUFFER(ctx->DrawBuffer)->color_table[((R) + (G) + (B))/3]



/**
 * Converts a GL window Y coord to an X window Y coord:
 */
#define YFLIP(XRB, Y)  ((XRB)->bottom - (Y))


/**
 * Return the address of a 1, 2 or 4-byte pixel in the buffer's XImage:
 * X==0 is left, Y==0 is bottom.
 */
#define PIXEL_ADDR1(XRB, X, Y)  \
   ( (XRB)->origin1 - (Y) * (XRB)->width1 + (X) )

#define PIXEL_ADDR2(XRB, X, Y)  \
   ( (XRB)->origin2 - (Y) * (XRB)->width2 + (X) )

#define PIXEL_ADDR3(XRB, X, Y)  \
   ( (bgr_t *) ( (XRB)->origin3 - (Y) * (XRB)->width3 + 3 * (X) ))

#define PIXEL_ADDR4(XRB, X, Y)  \
   ( (XRB)->origin4 - (Y) * (XRB)->width4 + (X) )



/*
 * External functions:
 */

extern struct xmesa_renderbuffer *
xmesa_new_renderbuffer(GLcontext *ctx, GLuint name, const GLvisual *visual,
                       GLboolean backBuffer);

extern void
xmesa_delete_framebuffer(struct gl_framebuffer *fb);

extern XMesaBuffer
xmesa_find_buffer(XMesaDisplay *dpy, XMesaColormap cmap, XMesaBuffer notThis);

extern unsigned long
xmesa_color_to_pixel( GLcontext *ctx,
                      GLubyte r, GLubyte g, GLubyte b, GLubyte a,
                      GLuint pixelFormat );

extern void
xmesa_get_window_size(XMesaDisplay *dpy, XMesaBuffer b,
                      GLuint *width, GLuint *height);

extern void
xmesa_check_and_update_buffer_size(XMesaContext xmctx, XMesaBuffer drawBuffer);

extern void
xmesa_init_driver_functions( XMesaVisual xmvisual,
                             struct dd_function_table *driver );

extern void
xmesa_update_state( GLcontext *ctx, GLbitfield new_state );

extern void
xmesa_set_renderbuffer_funcs(struct xmesa_renderbuffer *xrb,
                             enum pixel_format pixelformat, GLint depth);

extern void
xmesa_destroy_buffers_on_display(XMesaDisplay *dpy);


/**
 * Using a function instead of an ordinary cast is safer.
 */
static INLINE struct xmesa_renderbuffer *
xmesa_renderbuffer(struct gl_renderbuffer *rb)
{
   return (struct xmesa_renderbuffer *) rb;
}


/**
 * Return pointer to XMesaContext corresponding to a Mesa GLcontext.
 * Since we're using structure containment, it's just a cast!.
 */
static INLINE XMesaContext
XMESA_CONTEXT(GLcontext *ctx)
{
   return (XMesaContext) ctx;
}


/**
 * Return pointer to XMesaBuffer corresponding to a Mesa GLframebuffer.
 * Since we're using structure containment, it's just a cast!.
 */
static INLINE XMesaBuffer
XMESA_BUFFER(GLframebuffer *b)
{
   return (XMesaBuffer) b;
}


/* Plugged into the software rasterizer.  Try to use internal
 * swrast-style point, line and triangle functions.
 */
extern void xmesa_choose_point( GLcontext *ctx );
extern void xmesa_choose_line( GLcontext *ctx );
extern void xmesa_choose_triangle( GLcontext *ctx );


extern void xmesa_register_swrast_functions( GLcontext *ctx );



#define ENABLE_EXT_texure_compression_s3tc 0 /* SW texture compression */

#ifdef XFree86Server
#define ENABLE_EXT_timer_query 0
#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
#define ENABLE_EXT_timer_query 1 /* should have 64-bit GLuint64EXT */
#else
#define ENABLE_EXT_timer_query 0 /* may not have 64-bit GLuint64EXT */
#endif

#endif