sdl_dgavideo.c

Simple DirectMedia Layer - Simple DirectMedia Layer 是一个跨平台的多媒体库设计用来提供快速图形framebuffer和音频驱动。应用MPEG为软件

			surfaces_mem += screen_len;
			surfaces_len -= screen_len;
		}
	}

	/* Allocate memory tracking for hardware surfaces */
	DGA_FreeHWSurfaces(this);
	if ( surfaces_len < 0 ) {
		surfaces_len = 0;
	}
	DGA_InitHWSurfaces(this, current, surfaces_mem, surfaces_len);

	/* Expose the back buffer as surface memory */
	if ( current->flags & SDL_DOUBLEBUF ) {
		this->screen = current;
		DGA_FlipHWSurface(this, current);
		this->screen = NULL;
	}

	/* Set the update rectangle function */
	this->UpdateRects = DGA_DirectUpdate;

	/* Enable mouse and keyboard support */
	{ long input_mask;
	  input_mask = (KeyPressMask | KeyReleaseMask);
	  input_mask |= (ButtonPressMask | ButtonReleaseMask);
	  input_mask |= PointerMotionMask;
	  SDL_NAME(XDGASelectInput)(DGA_Display, DGA_Screen, input_mask);
	}

	/* We're done */
	return(current);
}

#ifdef DGA_DEBUG
static void DGA_DumpHWSurfaces(_THIS)
{
	vidmem_bucket *bucket;

	printf("Memory left: %d (%d total)\n", surfaces_memleft, surfaces_memtotal);
	printf("\n");
	printf("         Base  Size\n");
	for ( bucket=&surfaces; bucket; bucket=bucket->next ) {
		printf("Bucket:  %p, %d (%s)\n", bucket->base, bucket->size, bucket->used ? "used" : "free");
		if ( bucket->prev ) {
			if ( bucket->base != bucket->prev->base+bucket->prev->size ) {
				printf("Warning, corrupt bucket list! (prev)\n");
			}
		} else {
			if ( bucket != &surfaces ) {
				printf("Warning, corrupt bucket list! (!prev)\n");
			}
		}
		if ( bucket->next ) {
			if ( bucket->next->base != bucket->base+bucket->size ) {
				printf("Warning, corrupt bucket list! (next)\n");
			}
		}
	}
	printf("\n");
}
#endif

static int DGA_InitHWSurfaces(_THIS, SDL_Surface *screen, Uint8 *base, int size)
{
	vidmem_bucket *bucket;

	surfaces_memtotal = size;
	surfaces_memleft = size;

	if ( surfaces_memleft > 0 ) {
		bucket = (vidmem_bucket *)malloc(sizeof(*bucket));
		if ( bucket == NULL ) {
			SDL_OutOfMemory();
			return(-1);
		}
		bucket->prev = &surfaces;
		bucket->used = 0;
		bucket->dirty = 0;
		bucket->base = base;
		bucket->size = size;
		bucket->next = NULL;
	} else {
		bucket = NULL;
	}

	surfaces.prev = NULL;
	surfaces.used = 1;
	surfaces.dirty = 0;
	surfaces.base = screen->pixels;
	surfaces.size = (unsigned int)((long)base - (long)surfaces.base);
	surfaces.next = bucket;
	screen->hwdata = (struct private_hwdata *)&surfaces;
	return(0);
}
static void DGA_FreeHWSurfaces(_THIS)
{
	vidmem_bucket *bucket, *freeable;

	bucket = surfaces.next;
	while ( bucket ) {
		freeable = bucket;
		bucket = bucket->next;
		free(freeable);
	}
	surfaces.next = NULL;
}

static __inline__ void DGA_AddBusySurface(SDL_Surface *surface)
{
	((vidmem_bucket *)surface->hwdata)->dirty = 1;
}

static __inline__ int DGA_IsSurfaceBusy(SDL_Surface *surface)
{
	return ((vidmem_bucket *)surface->hwdata)->dirty;
}

static __inline__ void DGA_WaitBusySurfaces(_THIS)
{
	vidmem_bucket *bucket;

	/* Wait for graphic operations to complete */
	SDL_NAME(XDGASync)(DGA_Display, DGA_Screen);

	/* Clear all surface dirty bits */
	for ( bucket=&surfaces; bucket; bucket=bucket->next ) {
		bucket->dirty = 0;
	}
}

static int DGA_AllocHWSurface(_THIS, SDL_Surface *surface)
{
	vidmem_bucket *bucket;
	int size;
	int extra;
	int retval = 0;

/* Temporarily, we only allow surfaces the same width as display.
   Some blitters require the pitch between two hardware surfaces
   to be the same.  Others have interesting alignment restrictions.
*/
if ( surface->pitch > SDL_VideoSurface->pitch ) {
	SDL_SetError("Surface requested wider than screen");
	return(-1);
}
surface->pitch = SDL_VideoSurface->pitch;
	size = surface->h * surface->pitch;
#ifdef DGA_DEBUG
	fprintf(stderr, "Allocating bucket of %d bytes\n", size);
#endif
	LOCK_DISPLAY();

	/* Quick check for available mem */
	if ( size > surfaces_memleft ) {
		SDL_SetError("Not enough video memory");
		retval = -1;
		goto done;
	}

	/* Search for an empty bucket big enough */
	for ( bucket=&surfaces; bucket; bucket=bucket->next ) {
		if ( ! bucket->used && (size <= bucket->size) ) {
			break;
		}
	}
	if ( bucket == NULL ) {
		SDL_SetError("Video memory too fragmented");
		retval = -1;
		goto done;
	}

	/* Create a new bucket for left-over memory */
	extra = (bucket->size - size);
	if ( extra ) {
		vidmem_bucket *newbucket;

#ifdef DGA_DEBUG
	fprintf(stderr, "Adding new free bucket of %d bytes\n", extra);
#endif
		newbucket = (vidmem_bucket *)malloc(sizeof(*newbucket));
		if ( newbucket == NULL ) {
			SDL_OutOfMemory();
			retval = -1;
			goto done;
		}
		newbucket->prev = bucket;
		newbucket->used = 0;
		newbucket->base = bucket->base+size;
		newbucket->size = extra;
		newbucket->next = bucket->next;
		if ( bucket->next ) {
			bucket->next->prev = newbucket;
		}
		bucket->next = newbucket;
	}

	/* Set the current bucket values and return it! */
	bucket->used = 1;
	bucket->size = size;
	bucket->dirty = 0;
#ifdef DGA_DEBUG
	fprintf(stderr, "Allocated %d bytes at %p\n", bucket->size, bucket->base);
#endif
	surfaces_memleft -= size;
	surface->flags |= SDL_HWSURFACE;
	surface->pixels = bucket->base;
	surface->hwdata = (struct private_hwdata *)bucket;
done:
	UNLOCK_DISPLAY();
	return(retval);
}
static void DGA_FreeHWSurface(_THIS, SDL_Surface *surface)
{
	vidmem_bucket *bucket, *freeable;

	/* Look for the bucket in the current list */
	for ( bucket=&surfaces; bucket; bucket=bucket->next ) {
		if ( bucket == (vidmem_bucket *)surface->hwdata ) {
			break;
		}
	}
	if ( bucket && bucket->used ) {
		/* Add the memory back to the total */
#ifdef DGA_DEBUG
	printf("Freeing bucket of %d bytes\n", bucket->size);
#endif
		surfaces_memleft += bucket->size;

		/* Can we merge the space with surrounding buckets? */
		bucket->used = 0;
		if ( bucket->next && ! bucket->next->used ) {
#ifdef DGA_DEBUG
	printf("Merging with next bucket, for %d total bytes\n", bucket->size+bucket->next->size);
#endif
			freeable = bucket->next;
			bucket->size += bucket->next->size;
			bucket->next = bucket->next->next;
			if ( bucket->next ) {
				bucket->next->prev = bucket;
			}
			free(freeable);
		}
		if ( bucket->prev && ! bucket->prev->used ) {
#ifdef DGA_DEBUG
	printf("Merging with previous bucket, for %d total bytes\n", bucket->prev->size+bucket->size);
#endif
			freeable = bucket;
			bucket->prev->size += bucket->size;
			bucket->prev->next = bucket->next;
			if ( bucket->next ) {
				bucket->next->prev = bucket->prev;
			}
			free(freeable);
		}
	}
	surface->pixels = NULL;
	surface->hwdata = NULL;
}

static __inline__ void DGA_dst_to_xy(_THIS, SDL_Surface *dst, int *x, int *y)
{
	*x = (long)((Uint8 *)dst->pixels - memory_base)%memory_pitch;
	*y = (long)((Uint8 *)dst->pixels - memory_base)/memory_pitch;
}

static int DGA_FillHWRect(_THIS, SDL_Surface *dst, SDL_Rect *rect, Uint32 color)
{
	int x, y;
	unsigned int w, h;

	/* Don't fill the visible part of the screen, wait until flipped */
	LOCK_DISPLAY();
	if ( was_flipped && (dst == this->screen) ) {
		while ( SDL_NAME(XDGAGetViewportStatus)(DGA_Display, DGA_Screen) )
			/* Keep waiting for the hardware ... */ ;
		was_flipped = 0;
	}
	DGA_dst_to_xy(this, dst, &x, &y);
	x += rect->x;
	y += rect->y;
	w = rect->w;
	h = rect->h;
#if 0
  printf("Hardware accelerated rectangle fill: %dx%d at %d,%d\n", w, h, x, y);
#endif
	SDL_NAME(XDGAFillRectangle)(DGA_Display, DGA_Screen, x, y, w, h, color);
	XFlush(DGA_Display);
	DGA_AddBusySurface(dst);
	UNLOCK_DISPLAY();
	return(0);
}

static int HWAccelBlit(SDL_Surface *src, SDL_Rect *srcrect,
                       SDL_Surface *dst, SDL_Rect *dstrect)
{
	SDL_VideoDevice *this;
	int srcx, srcy;
	int dstx, dsty;
	unsigned int w, h;

	this = current_video;
	/* Don't blit to the visible part of the screen, wait until flipped */
	LOCK_DISPLAY();
	if ( was_flipped && (dst == this->screen) ) {
		while ( SDL_NAME(XDGAGetViewportStatus)(DGA_Display, DGA_Screen) )
			/* Keep waiting for the hardware ... */ ;
		was_flipped = 0;
	}
	DGA_dst_to_xy(this, src, &srcx, &srcy);
	srcx += srcrect->x;
	srcy += srcrect->y;
	DGA_dst_to_xy(this, dst, &dstx, &dsty);
	dstx += dstrect->x;
	dsty += dstrect->y;
	w = srcrect->w;
	h = srcrect->h;
#if 0
  printf("Blitting %dx%d from %d,%d to %d,%d\n", w, h, srcx, srcy, dstx, dsty);
#endif
	if ( (src->flags & SDL_SRCCOLORKEY) == SDL_SRCCOLORKEY ) {
		SDL_NAME(XDGACopyTransparentArea)(DGA_Display, DGA_Screen,
			srcx, srcy, w, h, dstx, dsty, src->format->colorkey);
	} else {
		SDL_NAME(XDGACopyArea)(DGA_Display, DGA_Screen,
			srcx, srcy, w, h, dstx, dsty);
	}
	XFlush(DGA_Display);
	DGA_AddBusySurface(src);
	DGA_AddBusySurface(dst);
	UNLOCK_DISPLAY();
	return(0);
}

static int DGA_CheckHWBlit(_THIS, SDL_Surface *src, SDL_Surface *dst)
{
	int accelerated;

	/* Set initial acceleration on */
	src->flags |= SDL_HWACCEL;

	/* Set the surface attributes */
	if ( (src->flags & SDL_SRCALPHA) == SDL_SRCALPHA ) {
		if ( ! this->info.blit_hw_A ) {
			src->flags &= ~SDL_HWACCEL;
		}
	}
	if ( (src->flags & SDL_SRCCOLORKEY) == SDL_SRCCOLORKEY ) {
		if ( ! this->info.blit_hw_CC ) {
			src->flags &= ~SDL_HWACCEL;
		}
	}

	/* Check to see if final surface blit is accelerated */
	accelerated = !!(src->flags & SDL_HWACCEL);
	if ( accelerated ) {
		src->map->hw_blit = HWAccelBlit;
	}
	return(accelerated);
}

static __inline__ void DGA_WaitFlip(_THIS)
{
	if ( was_flipped ) {
		while ( SDL_NAME(XDGAGetViewportStatus)(DGA_Display, DGA_Screen) )
			/* Keep waiting for the hardware ... */ ;
		was_flipped = 0;
	}
}

static int DGA_LockHWSurface(_THIS, SDL_Surface *surface)
{
	if ( surface == this->screen ) {
		SDL_mutexP(hw_lock);
		LOCK_DISPLAY();
		if ( DGA_IsSurfaceBusy(surface) ) {
			DGA_WaitBusySurfaces(this);
		}
		DGA_WaitFlip(this);
		UNLOCK_DISPLAY();
	} else {
		if ( DGA_IsSurfaceBusy(surface) ) {
			LOCK_DISPLAY();
			DGA_WaitBusySurfaces(this);
			UNLOCK_DISPLAY();
		}
	}
	return(0);
}
static void DGA_UnlockHWSurface(_THIS, SDL_Surface *surface)
{
	if ( surface == this->screen ) {
		SDL_mutexV(hw_lock);
	}
}

static int DGA_FlipHWSurface(_THIS, SDL_Surface *surface)
{
	/* Wait for vertical retrace and then flip display */
	LOCK_DISPLAY();
	if ( DGA_IsSurfaceBusy(this->screen) ) {
		DGA_WaitBusySurfaces(this);
	}
	DGA_WaitFlip(this);
	SDL_NAME(XDGASetViewport)(DGA_Display, DGA_Screen,
	                0, flip_yoffset[flip_page], XDGAFlipRetrace);
	XFlush(DGA_Display);
	UNLOCK_DISPLAY();
	was_flipped = 1;
	flip_page = !flip_page;

	surface->pixels = flip_address[flip_page];
	return(0);
}

static void DGA_DirectUpdate(_THIS, int numrects, SDL_Rect *rects)
{
	/* The application is already updating the visible video memory */
	return;
}

static int DGA_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors)
{
        int i;
	XColor  *xcmap;

	/* This happens on initialization */
	if ( ! DGA_colormap ) {
		return(0);
	}
	xcmap = (XColor *)alloca(ncolors*sizeof(*xcmap));
	for ( i=0; i<ncolors; ++i ) {
		xcmap[i].pixel = firstcolor + i;
		xcmap[i].red   = (colors[i].r<<8)|colors[i].r;
		xcmap[i].green = (colors[i].g<<8)|colors[i].g;
		xcmap[i].blue  = (colors[i].b<<8)|colors[i].b;
		xcmap[i].flags = (DoRed|DoGreen|DoBlue);
	}
	LOCK_DISPLAY();
	XStoreColors(DGA_Display, DGA_colormap, xcmap, ncolors);
	XSync(DGA_Display, False);
	UNLOCK_DISPLAY();

	/* That was easy. :) */
	return(1);
}

int DGA_SetGammaRamp(_THIS, Uint16 *ramp)
{
	int i, ncolors;
	XColor xcmap[256];

	/* See if actually setting the gamma is supported */
	if ( DGA_visualClass != DirectColor ) {
	    SDL_SetError("Gamma correction not supported on this visual");
	    return(-1);
	}

	/* Calculate the appropriate palette for the given gamma ramp */
	if ( this->screen->format->BitsPerPixel <= 16 ) {
		ncolors = 64; /* Is this right? */
	} else {
		ncolors = 256;
	}
	for ( i=0; i<ncolors; ++i ) {
		Uint8 c = (256 * i / ncolors);
		xcmap[i].pixel = SDL_MapRGB(this->screen->format, c, c, c);
		xcmap[i].red   = ramp[0*256+c];
		xcmap[i].green = ramp[1*256+c];
		xcmap[i].blue  = ramp[2*256+c];
		xcmap[i].flags = (DoRed|DoGreen|DoBlue);
	}
	LOCK_DISPLAY();
	XStoreColors(DGA_Display, DGA_colormap, xcmap, ncolors);
	XSync(DGA_Display, False);
	UNLOCK_DISPLAY();
	return(0);
}

void DGA_VideoQuit(_THIS)
{
	int i, j;

	if ( DGA_Display ) {
		/* Free colormap, if necessary */
		if ( DGA_colormap ) {
			XFreeColormap(DGA_Display, DGA_colormap);
			DGA_colormap = 0;
		}

		/* Unmap memory and reset video mode */
		SDL_NAME(XDGACloseFramebuffer)(DGA_Display, DGA_Screen);
		if ( this->screen ) {
			/* Tell SDL not to free the pixels */
			this->screen->pixels = NULL;
		}
		SDL_NAME(XDGASetMode)(DGA_Display, DGA_Screen, 0);

		/* Clear the lock mutex */
		if ( hw_lock != NULL ) {
			SDL_DestroyMutex(hw_lock);
			hw_lock = NULL;
		}
#ifdef LOCK_DGA_DISPLAY
		if ( event_lock != NULL ) {
			SDL_DestroyMutex(event_lock);
			event_lock = NULL;
		}
#endif /* LOCK_DGA_DISPLAY */


		/* Clean up defined video modes */
		for ( i=0; i<NUM_MODELISTS; ++i ) {
			if ( SDL_modelist[i] != NULL ) {
				for ( j=0; SDL_modelist[i][j]; ++j ) {
					free(SDL_modelist[i][j]);
				}
				free(SDL_modelist[i]);
				SDL_modelist[i] = NULL;
			}
		}

		/* Clean up the memory bucket list */
		DGA_FreeHWSurfaces(this);

		/* Close up the display */
		XCloseDisplay(DGA_Display);
	}
}