/*
 * Copyright © 2001 Keith Packard
 *
 * Partly based on code that is Copyright © The XFree86 Project Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Keith Packard not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Keith Packard makes no
 * representations about the suitability of this software for any purpose.  It
 * is provided "as is" without express or implied warranty.
 *
 * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#include <stdlib.h>

#include "uxa-priv.h"
#include <xorgVersion.h>

#ifdef RENDER
#include "mipict.h"

static void uxa_composite_fallback_pict_desc(PicturePtr pict, char *string,
					     int n)
{
	char format[20];
	char size[20];
	char loc;

	if (!pict) {
		snprintf(string, n, "None");
		return;
	}

	if (pict->pDrawable == NULL) {
		snprintf(string, n, "source-only");
		return;
	}

	switch (pict->format) {
	case PICT_a8r8g8b8:
		snprintf(format, 20, "ARGB8888");
		break;
	case PICT_x8r8g8b8:
		snprintf(format, 20, "XRGB8888");
		break;
	case PICT_r5g6b5:
		snprintf(format, 20, "RGB565  ");
		break;
	case PICT_x1r5g5b5:
		snprintf(format, 20, "RGB555  ");
		break;
	case PICT_a8:
		snprintf(format, 20, "A8      ");
		break;
	case PICT_a1:
		snprintf(format, 20, "A1      ");
		break;
	default:
		snprintf(format, 20, "0x%x", (int)pict->format);
		break;
	}

	loc = uxa_drawable_is_offscreen(pict->pDrawable) ? 's' : 'm';

	snprintf(size, 20, "%dx%d%s", pict->pDrawable->width,
		 pict->pDrawable->height, pict->repeat ? " R" : "");

	snprintf(string, n, "%p:%c fmt %s (%s)", pict->pDrawable, loc, format,
		 size);
}

static void
uxa_print_composite_fallback(CARD8 op,
			     PicturePtr pSrc, PicturePtr pMask, PicturePtr pDst)
{
	char sop[20];
	char srcdesc[40], maskdesc[40], dstdesc[40];

	switch (op) {
	case PictOpSrc:
		sprintf(sop, "Src");
		break;
	case PictOpOver:
		sprintf(sop, "Over");
		break;
	default:
		sprintf(sop, "0x%x", (int)op);
		break;
	}

	uxa_composite_fallback_pict_desc(pSrc, srcdesc, 40);
	uxa_composite_fallback_pict_desc(pMask, maskdesc, 40);
	uxa_composite_fallback_pict_desc(pDst, dstdesc, 40);

	ErrorF("Composite fallback: op %s, \n"
	       "                    src  %s, \n"
	       "                    mask %s, \n"
	       "                    dst  %s, \n",
	       sop, srcdesc, maskdesc, dstdesc);
}

Bool uxa_op_reads_destination(CARD8 op)
{
	/* FALSE (does not read destination) is the list of ops in the protocol
	 * document with "0" in the "Fb" column and no "Ab" in the "Fa" column.
	 * That's just Clear and Src.  ReduceCompositeOp() will already have
	 * converted con/disjoint clear/src to Clear or Src.
	 */
	switch (op) {
	case PictOpClear:
	case PictOpSrc:
		return FALSE;
	default:
		return TRUE;
	}
}

static Bool
uxa_get_pixel_from_rgba(CARD32 * pixel,
			CARD16 red,
			CARD16 green, CARD16 blue, CARD16 alpha, CARD32 format)
{
	int rbits, bbits, gbits, abits;
	int rshift, bshift, gshift, ashift;

	*pixel = 0;

	if (!PICT_FORMAT_COLOR(format))
		return FALSE;

	rbits = PICT_FORMAT_R(format);
	gbits = PICT_FORMAT_G(format);
	bbits = PICT_FORMAT_B(format);
	abits = PICT_FORMAT_A(format);

	if (PICT_FORMAT_TYPE(format) == PICT_TYPE_ARGB) {
		bshift = 0;
		gshift = bbits;
		rshift = gshift + gbits;
		ashift = rshift + rbits;
	} else {		/* PICT_TYPE_ABGR */
		rshift = 0;
		gshift = rbits;
		bshift = gshift + gbits;
		ashift = bshift + bbits;
	}

	*pixel |= (blue >> (16 - bbits)) << bshift;
	*pixel |= (red >> (16 - rbits)) << rshift;
	*pixel |= (green >> (16 - gbits)) << gshift;
	*pixel |= (alpha >> (16 - abits)) << ashift;

	return TRUE;
}

static Bool
uxa_get_rgba_from_pixel(CARD32 pixel,
			CARD16 * red,
			CARD16 * green,
			CARD16 * blue, CARD16 * alpha, CARD32 format)
{
	int rbits, bbits, gbits, abits;
	int rshift, bshift, gshift, ashift;

	if (!PICT_FORMAT_COLOR(format))
		return FALSE;

	rbits = PICT_FORMAT_R(format);
	gbits = PICT_FORMAT_G(format);
	bbits = PICT_FORMAT_B(format);
	abits = PICT_FORMAT_A(format);

	if (PICT_FORMAT_TYPE(format) == PICT_TYPE_ARGB) {
		bshift = 0;
		gshift = bbits;
		rshift = gshift + gbits;
		ashift = rshift + rbits;
	} else {		/* PICT_TYPE_ABGR */
		rshift = 0;
		gshift = rbits;
		bshift = gshift + gbits;
		ashift = bshift + bbits;
	}

	*red = ((pixel >> rshift) & ((1 << rbits) - 1)) << (16 - rbits);
	while (rbits < 16) {
		*red |= *red >> rbits;
		rbits <<= 1;
	}

	*green = ((pixel >> gshift) & ((1 << gbits) - 1)) << (16 - gbits);
	while (gbits < 16) {
		*green |= *green >> gbits;
		gbits <<= 1;
	}

	*blue = ((pixel >> bshift) & ((1 << bbits) - 1)) << (16 - bbits);
	while (bbits < 16) {
		*blue |= *blue >> bbits;
		bbits <<= 1;
	}

	if (abits) {
		*alpha =
		    ((pixel >> ashift) & ((1 << abits) - 1)) << (16 - abits);
		while (abits < 16) {
			*alpha |= *alpha >> abits;
			abits <<= 1;
		}
	} else
		*alpha = 0xffff;

	return TRUE;
}

static int
uxa_try_driver_solid_fill(PicturePtr pSrc,
			  PicturePtr pDst,
			  INT16 xSrc,
			  INT16 ySrc,
			  INT16 xDst, INT16 yDst, CARD16 width, CARD16 height)
{
	uxa_screen_t *uxa_screen = uxa_get_screen(pDst->pDrawable->pScreen);
	RegionRec region;
	BoxPtr pbox;
	int nbox;
	int dst_off_x, dst_off_y;
	PixmapPtr pSrcPix, pDstPix;
	CARD32 pixel;
	CARD16 red, green, blue, alpha;

	pDstPix = uxa_get_drawable_pixmap(pDst->pDrawable);
	pSrcPix = uxa_get_drawable_pixmap(pSrc->pDrawable);

	xDst += pDst->pDrawable->x;
	yDst += pDst->pDrawable->y;
	xSrc += pSrc->pDrawable->x;
	ySrc += pSrc->pDrawable->y;

	if (!miComputeCompositeRegion(&region, pSrc, NULL, pDst,
				      xSrc, ySrc, 0, 0, xDst, yDst,
				      width, height))
		return 1;

	uxa_get_drawable_deltas(pDst->pDrawable, pDstPix, &dst_off_x,
				&dst_off_y);

	REGION_TRANSLATE(pScreen, &region, dst_off_x, dst_off_y);

	pixel = uxa_get_pixmap_first_pixel(pSrcPix);

	if (!uxa_pixmap_is_offscreen(pDstPix)) {
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);
		return 0;
	}

	if (!uxa_get_rgba_from_pixel(pixel, &red, &green, &blue, &alpha,
				     pSrc->format)) {
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);
		return -1;
	}

	if (!uxa_get_pixel_from_rgba(&pixel, red, green, blue, alpha,
				     pDst->format)) {
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);
		return -1;
	}

	if (!(*uxa_screen->info->prepare_solid)
	    (pDstPix, GXcopy, 0xffffffff, pixel)) {
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);
		return -1;
	}

	nbox = REGION_NUM_RECTS(&region);
	pbox = REGION_RECTS(&region);

	while (nbox--) {
		(*uxa_screen->info->solid) (pDstPix, pbox->x1, pbox->y1,
					    pbox->x2, pbox->y2);
		pbox++;
	}

	(*uxa_screen->info->done_solid) (pDstPix);

	REGION_UNINIT(pDst->pDrawable->pScreen, &region);
	return 1;
}

/* In order to avoid fallbacks when using an a1 source/mask,
 * for example with non-antialiased trapezoids, we need to
 * expand the bitmap into an a8 Picture. We do so by using the generic
 * composition routines, which while may not be perfect is far faster
 * than causing a fallback.
 */
static PicturePtr
uxa_picture_from_a1_pixman_image(ScreenPtr pScreen, pixman_image_t * image)
{
	PicturePtr pPicture;
	PicturePtr pSrc;
	PixmapPtr pPixmap;
	int width, height;
	int error;

	width = pixman_image_get_width(image);
	height = pixman_image_get_height(image);

	pPixmap = (*pScreen->CreatePixmap) (pScreen, width, height, 8,
					    UXA_CREATE_PIXMAP_FOR_MAP);
	if (!pPixmap)
		return 0;

	pPicture = CreatePicture(0, &pPixmap->drawable,
				 PictureMatchFormat(pScreen, 8, PICT_a8),
				 0, 0, serverClient, &error);
	(*pScreen->DestroyPixmap) (pPixmap);
	if (!pPicture)
		return 0;

	ValidatePicture(pPicture);

	pPixmap = GetScratchPixmapHeader(pScreen, width, height, 1,
					 BitsPerPixel(1),
					 pixman_image_get_stride(image),
					 pixman_image_get_data(image));
	if (!pPixmap) {
		FreePicture(pPicture, 0);
		return 0;
	}

	pSrc = CreatePicture(0, &pPixmap->drawable,
			     PictureMatchFormat(pScreen, 1, PICT_a1),
			     0, 0, serverClient, &error);
	FreeScratchPixmapHeader(pPixmap);
	if (!pSrc) {
		FreePicture(pPicture, 0);
		return 0;
	}

	CompositePicture(PictOpSrc, pSrc, NULL, pPicture,
			 0, 0, 0, 0, 0, 0, width, height);

	FreePicture(pSrc, 0);

	return pPicture;
}

static PicturePtr
uxa_picture_from_pixman_image(ScreenPtr pScreen,
			      pixman_image_t * image,
			      pixman_format_code_t format)
{
	PicturePtr pPicture;
	PixmapPtr pPixmap;
	GCPtr pGC;
	int width, height, depth;
	int error;

	if (format == PICT_a1)
		return uxa_picture_from_a1_pixman_image(pScreen, image);

	width = pixman_image_get_width(image);
	height = pixman_image_get_height(image);
	depth = pixman_image_get_depth(image);

	pPixmap = (*pScreen->CreatePixmap) (pScreen, width, height, depth,
					    UXA_CREATE_PIXMAP_FOR_MAP);
	if (!pPixmap)
		return 0;

	pPicture = CreatePicture(0, &pPixmap->drawable,
				 PictureMatchFormat(pScreen, depth, format),
				 0, 0, serverClient, &error);
	(*pScreen->DestroyPixmap) (pPixmap);
	if (!pPicture)
		return 0;

	ValidatePicture(pPicture);

	pPixmap = GetScratchPixmapHeader(pScreen, width, height, depth,
					 BitsPerPixel(depth),
					 pixman_image_get_stride(image),
					 pixman_image_get_data(image));
	if (!pPixmap) {
		FreePicture(pPicture, 0);
		return 0;
	}

	pGC = GetScratchGC(depth, pScreen);
	if (!pGC) {
		FreeScratchPixmapHeader(pPixmap);
		FreePicture(pPicture, 0);
		return 0;
	}
	ValidateGC(pPicture->pDrawable, pGC);

	(*pGC->ops->CopyArea) (&pPixmap->drawable, pPicture->pDrawable,
			       pGC, 0, 0, width, height, 0, 0);

	FreeScratchGC(pGC);
	FreeScratchPixmapHeader(pPixmap);

	return pPicture;
}

#if XORG_VERSION_CURRENT < XORG_VERSION_NUMERIC (1,6,99,1,0)
#define IMAGE_FROM_PICT(P) image_from_pict(P, 0)
#else
#define IMAGE_FROM_PICT(P) image_from_pict(P, 0, 0)
#endif

static PicturePtr
uxa_acquire_pattern(ScreenPtr pScreen,
		    PicturePtr pPict,
		    pixman_format_code_t format,
		    INT16 x, INT16 y, CARD16 width, CARD16 height)
{
	pixman_image_t *source, *image;

	source = IMAGE_FROM_PICT(pPict);
	if (!source)
		return 0;

	image = pixman_image_create_bits(format, width, height, NULL, 0);
	if (!image) {
		pixman_image_unref(source);
		return 0;
	}

	pixman_image_composite(PIXMAN_OP_SRC,
			       source, NULL, image,
			       x, y, 0, 0, 0, 0, width, height);
	pixman_image_unref(source);

	pPict = uxa_picture_from_pixman_image(pScreen, image, format);
	pixman_image_unref(image);

	return pPict;
}

static PicturePtr
uxa_acquire_source(ScreenPtr pScreen,
		   PicturePtr pPict,
		   INT16 x, INT16 y,
		   CARD16 width, CARD16 height, INT16 * out_x, INT16 * out_y)
{
	if (pPict->pDrawable) {
		*out_x = x + pPict->pDrawable->x;
		*out_y = y + pPict->pDrawable->y;
		return pPict;
	}

	*out_x = 0;
	*out_y = 0;
	return uxa_acquire_pattern(pScreen, pPict,
				   PICT_a8r8g8b8, x, y, width, height);
}

static PicturePtr
uxa_acquire_mask(ScreenPtr pScreen,
		 PicturePtr pPict,
		 INT16 x, INT16 y,
		 INT16 width, INT16 height, INT16 * out_x, INT16 * out_y)
{
	if (pPict->pDrawable) {
		*out_x = x + pPict->pDrawable->x;
		*out_y = y + pPict->pDrawable->y;
		return pPict;
	}

	*out_x = 0;
	*out_y = 0;
	return uxa_acquire_pattern(pScreen, pPict,
				   PICT_a8, x, y, width, height);
}

static int
uxa_try_driver_composite_rects(CARD8 op,
			       PicturePtr pSrc,
			       PicturePtr pDst,
			       int nrect, uxa_composite_rect_t * rects)
{
	uxa_screen_t *uxa_screen = uxa_get_screen(pDst->pDrawable->pScreen);
	int src_off_x, src_off_y, dst_off_x, dst_off_y;
	PixmapPtr pSrcPix, pDstPix;

	if (!uxa_screen->info->prepare_composite || uxa_screen->swappedOut)
		return -1;

	if (uxa_screen->info->check_composite &&
	    !(*uxa_screen->info->check_composite) (op, pSrc, NULL, pDst)) {
		return -1;
	}

	pDstPix =
	    uxa_get_offscreen_pixmap(pDst->pDrawable, &dst_off_x, &dst_off_y);
	if (!pDstPix)
		return 0;

	pSrcPix =
	    uxa_get_offscreen_pixmap(pSrc->pDrawable, &src_off_x, &src_off_y);
	if (!pSrcPix)
		return 0;

	if (!(*uxa_screen->info->prepare_composite)
	    (op, pSrc, NULL, pDst, pSrcPix, NULL, pDstPix))
		return -1;

	while (nrect--) {
		INT16 xDst = rects->xDst + pDst->pDrawable->x;
		INT16 yDst = rects->yDst + pDst->pDrawable->y;
		INT16 xSrc = rects->xSrc + pSrc->pDrawable->x;
		INT16 ySrc = rects->ySrc + pSrc->pDrawable->y;

		RegionRec region;
		BoxPtr pbox;
		int nbox;

		if (!miComputeCompositeRegion(&region, pSrc, NULL, pDst,
					      xSrc, ySrc, 0, 0, xDst, yDst,
					      rects->width, rects->height))
			goto next_rect;

		REGION_TRANSLATE(pScreen, &region, dst_off_x, dst_off_y);

		nbox = REGION_NUM_RECTS(&region);
		pbox = REGION_RECTS(&region);

		xSrc = xSrc + src_off_x - xDst - dst_off_x;
		ySrc = ySrc + src_off_y - yDst - dst_off_y;

		while (nbox--) {
			(*uxa_screen->info->composite) (pDstPix,
							pbox->x1 + xSrc,
							pbox->y1 + ySrc,
							0, 0,
							pbox->x1,
							pbox->y1,
							pbox->x2 - pbox->x1,
							pbox->y2 - pbox->y1);
			pbox++;
		}

next_rect:
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);

		rects++;
	}
	(*uxa_screen->info->done_composite) (pDstPix);

	return 1;
}

/**
 * Copy a number of rectangles from source to destination in a single
 * operation. This is specialized for building a glyph mask: we don'y
 * have a mask argument because we don't need it for that, and we
 * don't have he special-case fallbacks found in uxa_composite() - if the
 * driver can support it, we use the driver functionality, otherwise we
 * fallback straight to software.
 */
void
uxa_composite_rects(CARD8 op,
		    PicturePtr pSrc,
		    PicturePtr pDst, int nrect, uxa_composite_rect_t * rects)
{
	int n;
	uxa_composite_rect_t *r;

    /************************************************************/

	ValidatePicture(pSrc);
	ValidatePicture(pDst);

	if (uxa_try_driver_composite_rects(op, pSrc, pDst, nrect, rects) != 1) {
		n = nrect;
		r = rects;
		while (n--) {
			uxa_check_composite(op, pSrc, NULL, pDst,
					    r->xSrc, r->ySrc,
					    0, 0,
					    r->xDst, r->yDst,
					    r->width, r->height);
			r++;
		}
	}

    /************************************************************/

}

static int
uxa_try_driver_composite(CARD8 op,
			 PicturePtr pSrc,
			 PicturePtr pMask,
			 PicturePtr pDst,
			 INT16 xSrc,
			 INT16 ySrc,
			 INT16 xMask,
			 INT16 yMask,
			 INT16 xDst, INT16 yDst, CARD16 width, CARD16 height)
{
	uxa_screen_t *uxa_screen = uxa_get_screen(pDst->pDrawable->pScreen);
	RegionRec region;
	BoxPtr pbox;
	int nbox;
	int src_off_x, src_off_y, mask_off_x, mask_off_y, dst_off_x, dst_off_y;
	PixmapPtr pSrcPix, pMaskPix = NULL, pDstPix;
	PicturePtr localSrc, localMask = NULL;

	xDst += pDst->pDrawable->x;
	yDst += pDst->pDrawable->y;

	localSrc = uxa_acquire_source(pDst->pDrawable->pScreen,
				      pSrc, xSrc, ySrc, width, height,
				      &xSrc, &ySrc);
	if (!localSrc)
		return 0;

	if (pMask) {
		localMask = uxa_acquire_mask(pDst->pDrawable->pScreen,
					     pMask, xMask, yMask, width, height,
					     &xMask, &yMask);
		if (!localMask) {
			if (localSrc != pSrc)
				FreePicture(localSrc, 0);

			return 0;
		}
	}

	if (uxa_screen->info->check_composite &&
	    !(*uxa_screen->info->check_composite) (op, localSrc, localMask,
						   pDst)) {
		if (localSrc != pSrc)
			FreePicture(localSrc, 0);
		if (localMask && localMask != pMask)
			FreePicture(localMask, 0);

		return -1;
	}

	if (!miComputeCompositeRegion(&region, localSrc, localMask, pDst,
				      xSrc, ySrc, xMask, yMask, xDst, yDst,
				      width, height)) {
		if (localSrc != pSrc)
			FreePicture(localSrc, 0);
		if (localMask && localMask != pMask)
			FreePicture(localMask, 0);

		return 1;
	}

	pDstPix =
	    uxa_get_offscreen_pixmap(pDst->pDrawable, &dst_off_x, &dst_off_y);

	pSrcPix = uxa_get_offscreen_pixmap(localSrc->pDrawable,
					   &src_off_x, &src_off_y);

	if (localMask)
		pMaskPix = uxa_get_offscreen_pixmap(localMask->pDrawable,
						    &mask_off_x, &mask_off_y);

	if (!pDstPix || !pSrcPix || (localMask && !pMaskPix)) {
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);

		if (localSrc != pSrc)
			FreePicture(localSrc, 0);
		if (localMask && localMask != pMask)
			FreePicture(localMask, 0);

		return 0;
	}

	REGION_TRANSLATE(pScreen, &region, dst_off_x, dst_off_y);

	if (!(*uxa_screen->info->prepare_composite)
	    (op, localSrc, localMask, pDst, pSrcPix, pMaskPix, pDstPix)) {
		REGION_UNINIT(pDst->pDrawable->pScreen, &region);

		if (localSrc != pSrc)
			FreePicture(localSrc, 0);
		if (localMask && localMask != pMask)
			FreePicture(localMask, 0);

		return -1;
	}

	nbox = REGION_NUM_RECTS(&region);
	pbox = REGION_RECTS(&region);

	xMask = xMask + mask_off_x - xDst - dst_off_x;
	yMask = yMask + mask_off_y - yDst - dst_off_y;

	xSrc = xSrc + src_off_x - xDst - dst_off_x;
	ySrc = ySrc + src_off_y - yDst - dst_off_y;

	while (nbox--) {
		(*uxa_screen->info->composite) (pDstPix,
						pbox->x1 + xSrc,
						pbox->y1 + ySrc,
						pbox->x1 + xMask,
						pbox->y1 + yMask,
						pbox->x1,
						pbox->y1,
						pbox->x2 - pbox->x1,
						pbox->y2 - pbox->y1);
		pbox++;
	}
	(*uxa_screen->info->done_composite) (pDstPix);

	REGION_UNINIT(pDst->pDrawable->pScreen, &region);

	if (localSrc != pSrc)
		FreePicture(localSrc, 0);
	if (localMask && localMask != pMask)
		FreePicture(localMask, 0);

	return 1;
}

/**
 * uxa_try_magic_two_pass_composite_helper implements PictOpOver using two passes of
 * simpler operations PictOpOutReverse and PictOpAdd. Mainly used for component
 * alpha and limited 1-tmu cards.
 *
 * From http://anholt.livejournal.com/32058.html:
 *
 * The trouble is that component-alpha rendering requires two different sources
 * for blending: one for the source value to the blender, which is the
 * per-channel multiplication of source and mask, and one for the source alpha
 * for multiplying with the destination channels, which is the multiplication
 * of the source channels by the mask alpha. So the equation for Over is:
 *
 * dst.A = src.A * mask.A + (1 - (src.A * mask.A)) * dst.A
 * dst.R = src.R * mask.R + (1 - (src.A * mask.R)) * dst.R
 * dst.G = src.G * mask.G + (1 - (src.A * mask.G)) * dst.G
 * dst.B = src.B * mask.B + (1 - (src.A * mask.B)) * dst.B
 *
 * But we can do some simpler operations, right? How about PictOpOutReverse,
 * which has a source factor of 0 and dest factor of (1 - source alpha). We
 * can get the source alpha value (srca.X = src.A * mask.X) out of the texture
 * blenders pretty easily. So we can do a component-alpha OutReverse, which
 * gets us:
 *
 * dst.A = 0 + (1 - (src.A * mask.A)) * dst.A
 * dst.R = 0 + (1 - (src.A * mask.R)) * dst.R
 * dst.G = 0 + (1 - (src.A * mask.G)) * dst.G
 * dst.B = 0 + (1 - (src.A * mask.B)) * dst.B
 *
 * OK. And if an op doesn't use the source alpha value for the destination
 * factor, then we can do the channel multiplication in the texture blenders
 * to get the source value, and ignore the source alpha that we wouldn't use.
 * We've supported this in the Radeon driver for a long time. An example would
 * be PictOpAdd, which does:
 *
 * dst.A = src.A * mask.A + dst.A
 * dst.R = src.R * mask.R + dst.R
 * dst.G = src.G * mask.G + dst.G
 * dst.B = src.B * mask.B + dst.B
 *
 * Hey, this looks good! If we do a PictOpOutReverse and then a PictOpAdd right
 * after it, we get:
 *
 * dst.A = src.A * mask.A + ((1 - (src.A * mask.A)) * dst.A)
 * dst.R = src.R * mask.R + ((1 - (src.A * mask.R)) * dst.R)
 * dst.G = src.G * mask.G + ((1 - (src.A * mask.G)) * dst.G)
 * dst.B = src.B * mask.B + ((1 - (src.A * mask.B)) * dst.B)
 */

static int
uxa_try_magic_two_pass_composite_helper(CARD8 op,
					PicturePtr pSrc,
					PicturePtr pMask,
					PicturePtr pDst,
					INT16 xSrc,
					INT16 ySrc,
					INT16 xMask,
					INT16 yMask,
					INT16 xDst,
					INT16 yDst, CARD16 width, CARD16 height)
{
	uxa_screen_t *uxa_screen = uxa_get_screen(pDst->pDrawable->pScreen);

	assert(op == PictOpOver);

	if (uxa_screen->info->check_composite &&
	    (!(*uxa_screen->info->check_composite) (PictOpOutReverse, pSrc,
						    pMask, pDst)
	     || !(*uxa_screen->info->check_composite) (PictOpAdd, pSrc, pMask,
						       pDst))) {
		return -1;
	}

	/* Now, we think we should be able to accelerate this operation. First,
	 * composite the destination to be the destination times the source alpha
	 * factors.
	 */
	uxa_composite(PictOpOutReverse, pSrc, pMask, pDst, xSrc, ySrc, xMask,
		      yMask, xDst, yDst, width, height);

	/* Then, add in the source value times the destination alpha factors (1.0).
	 */
	uxa_composite(PictOpAdd, pSrc, pMask, pDst, xSrc, ySrc, xMask, yMask,
		      xDst, yDst, width, height);

	return 1;
}

void
uxa_composite(CARD8 op,
	      PicturePtr pSrc,
	      PicturePtr pMask,
	      PicturePtr pDst,
	      INT16 xSrc,
	      INT16 ySrc,
	      INT16 xMask,
	      INT16 yMask, INT16 xDst, INT16 yDst, CARD16 width, CARD16 height)
{
	uxa_screen_t *uxa_screen = uxa_get_screen(pDst->pDrawable->pScreen);
	int ret = -1;
	Bool saveSrcRepeat = pSrc->repeat;
	Bool saveMaskRepeat = pMask ? pMask->repeat : 0;
	RegionRec region;

	if (uxa_screen->swappedOut)
		goto fallback;

	if (pSrc->pDrawable == NULL || (pMask && pMask->pDrawable == NULL))
		goto composite;

	/* Remove repeat in source if useless */
	if (pSrc->repeat && !pSrc->transform && xSrc >= 0 &&
	    (xSrc + width) <= pSrc->pDrawable->width && ySrc >= 0 &&
	    (ySrc + height) <= pSrc->pDrawable->height)
		pSrc->repeat = 0;

	if (!pMask) {
		if ((op == PictOpSrc &&
		     ((pSrc->format == pDst->format) ||
		      (pSrc->format == PICT_a8r8g8b8
		       && pDst->format == PICT_x8r8g8b8)
		      || (pSrc->format == PICT_a8b8g8r8
			  && pDst->format == PICT_x8b8g8r8)))
		    || (op == PictOpOver && !pSrc->alphaMap && !pDst->alphaMap
			&& pSrc->format == pDst->format
			&& (pSrc->format == PICT_x8r8g8b8
			    || pSrc->format == PICT_x8b8g8r8))) {
			if (pSrc->pDrawable->width == 1
			    && pSrc->pDrawable->height == 1 && pSrc->repeat) {
				ret =
				    uxa_try_driver_solid_fill(pSrc, pDst, xSrc,
							      ySrc, xDst, yDst,
							      width, height);
				if (ret == 1)
					goto done;
			} else if (pSrc->pDrawable != NULL &&
				   !pSrc->repeat && !pSrc->transform) {
				xDst += pDst->pDrawable->x;
				yDst += pDst->pDrawable->y;
				xSrc += pSrc->pDrawable->x;
				ySrc += pSrc->pDrawable->y;

				if (!miComputeCompositeRegion
				    (&region, pSrc, pMask, pDst, xSrc, ySrc,
				     xMask, yMask, xDst, yDst, width, height))
					goto done;

				uxa_copy_n_to_n(pSrc->pDrawable,
						pDst->pDrawable, NULL,
						REGION_RECTS(&region),
						REGION_NUM_RECTS(&region),
						xSrc - xDst, ySrc - yDst, FALSE,
						FALSE, 0, NULL);
				REGION_UNINIT(pDst->pDrawable->pScreen,
					      &region);
				goto done;
			} else if (pSrc->pDrawable != NULL &&
				   pSrc->pDrawable->type == DRAWABLE_PIXMAP &&
				   !pSrc->transform &&
				   pSrc->repeatType == RepeatNormal) {
				DDXPointRec patOrg;

				/* Let's see if the driver can do the repeat
				 * in one go
				 */
				if (uxa_screen->info->prepare_composite
				    && !pSrc->alphaMap && !pDst->alphaMap) {
					ret =
					    uxa_try_driver_composite(op, pSrc,
								     pMask,
								     pDst, xSrc,
								     ySrc,
								     xMask,
								     yMask,
								     xDst, yDst,
								     width,
								     height);
					if (ret == 1)
						goto done;
				}

				/* Now see if we can use
				 * uxa_fill_region_tiled()
				 */
				xDst += pDst->pDrawable->x;
				yDst += pDst->pDrawable->y;
				xSrc += pSrc->pDrawable->x;
				ySrc += pSrc->pDrawable->y;

				if (!miComputeCompositeRegion
				    (&region, pSrc, pMask, pDst, xSrc, ySrc,
				     xMask, yMask, xDst, yDst, width, height))
					goto done;

				/* pattern origin is the point in the
				 * destination drawable
				 * corresponding to (0,0) in the source */
				patOrg.x = xDst - xSrc;
				patOrg.y = yDst - ySrc;

				ret =
				    uxa_fill_region_tiled(pDst->pDrawable,
							  &region,
							  (PixmapPtr) pSrc->
							  pDrawable, &patOrg,
							  FB_ALLONES, GXcopy);

				REGION_UNINIT(pDst->pDrawable->pScreen,
					      &region);

				if (ret)
					goto done;
			}
		}
	}

composite:
	/* Remove repeat in mask if useless */
	if (pMask && pMask->repeat && !pMask->transform && pMask->pDrawable &&
	    xMask >= 0 && (xMask + width) <= pMask->pDrawable->width &&
	    yMask >= 0 && (yMask + height) <= pMask->pDrawable->height)
		pMask->repeat = 0;

	if (uxa_screen->info->prepare_composite &&
	    !pSrc->alphaMap && (!pMask || !pMask->alphaMap) && !pDst->alphaMap)
	{
		Bool isSrcSolid;

		ret =
		    uxa_try_driver_composite(op, pSrc, pMask, pDst, xSrc, ySrc,
					     xMask, yMask, xDst, yDst, width,
					     height);
		if (ret == 1)
			goto done;

		/* For generic masks and solid src pictures, mach64 can do
		 * Over in two passes, similar to the component-alpha case.
		 */
		isSrcSolid = pSrc->pDrawable &&
		    pSrc->pDrawable->width == 1 &&
		    pSrc->pDrawable->height == 1 && pSrc->repeat;

		/* If we couldn't do the Composite in a single pass, and it
		 * was a component-alpha Over, see if we can do it in two
		 * passes with an OutReverse and then an Add.
		 */
		if (ret == -1 && op == PictOpOver && pMask &&
		    (pMask->componentAlpha || isSrcSolid)) {
			ret =
			    uxa_try_magic_two_pass_composite_helper(op, pSrc,
								    pMask, pDst,
								    xSrc, ySrc,
								    xMask,
								    yMask, xDst,
								    yDst, width,
								    height);
			if (ret == 1)
				goto done;
		}
	}

fallback:
	if (uxa_screen->fallback_debug)
		uxa_print_composite_fallback(op, pSrc, pMask, pDst);

	uxa_check_composite(op, pSrc, pMask, pDst, xSrc, ySrc,
			    xMask, yMask, xDst, yDst, width, height);

done:
	pSrc->repeat = saveSrcRepeat;
	if (pMask)
		pMask->repeat = saveMaskRepeat;
}
#endif

/**
 * Same as miCreateAlphaPicture, except it uses uxa_check_poly_fill_rect instead
 * of PolyFillRect to initialize the pixmap after creating it, to prevent
 * the pixmap from being migrated.
 *
 * See the comments about uxa_trapezoids and uxa_triangles.
 */
static PicturePtr
uxa_create_alpha_picture(ScreenPtr pScreen,
			 PicturePtr pDst,
			 PictFormatPtr pPictFormat, CARD16 width, CARD16 height)
{
	PixmapPtr pPixmap;
	PicturePtr pPicture;
	int error;

	if (width > 32767 || height > 32767)
		return 0;

	if (!pPictFormat) {
		if (pDst->polyEdge == PolyEdgeSharp)
			pPictFormat = PictureMatchFormat(pScreen, 1, PICT_a1);
		else
			pPictFormat = PictureMatchFormat(pScreen, 8, PICT_a8);
		if (!pPictFormat)
			return 0;
	}

	pPixmap = (*pScreen->CreatePixmap) (pScreen, width, height,
					    pPictFormat->depth,
					    UXA_CREATE_PIXMAP_FOR_MAP);
	if (!pPixmap)
		return 0;
	pPicture = CreatePicture(0, &pPixmap->drawable, pPictFormat,
				 0, 0, serverClient, &error);
	(*pScreen->DestroyPixmap) (pPixmap);
	return pPicture;
}

/**
 * uxa_trapezoids is essentially a copy of miTrapezoids that uses
 * uxa_create_alpha_picture instead of miCreateAlphaPicture.
 *
 * The problem with miCreateAlphaPicture is that it calls PolyFillRect
 * to initialize the contents after creating the pixmap, which
 * causes the pixmap to be moved in for acceleration. The subsequent
 * call to RasterizeTrapezoid won't be accelerated however, which
 * forces the pixmap to be moved out again.
 *
 * uxa_create_alpha_picture avoids this roundtrip by using
 * uxa_check_poly_fill_rect to initialize the contents.
 */
void
uxa_trapezoids(CARD8 op, PicturePtr pSrc, PicturePtr pDst,
	       PictFormatPtr maskFormat, INT16 xSrc, INT16 ySrc,
	       int ntrap, xTrapezoid * traps)
{
	ScreenPtr pScreen = pDst->pDrawable->pScreen;
	PictureScreenPtr ps = GetPictureScreen(pScreen);
	BoxRec bounds;
	Bool direct = op == PictOpAdd && miIsSolidAlpha(pSrc);

	if (maskFormat || direct) {
		miTrapezoidBounds(ntrap, traps, &bounds);

		if (bounds.y1 >= bounds.y2 || bounds.x1 >= bounds.x2)
			return;
	}

	/*
	 * Check for solid alpha add
	 */
	if (direct) {
		DrawablePtr pDraw = pDst->pDrawable;
		PixmapPtr pixmap = uxa_get_drawable_pixmap(pDraw);
		int xoff, yoff;

		uxa_get_drawable_deltas(pDraw, pixmap, &xoff, &yoff);

		xoff += pDraw->x;
		yoff += pDraw->y;

		if (uxa_prepare_access(pDraw, UXA_ACCESS_RW)) {
			for (; ntrap; ntrap--, traps++)
				(*ps->RasterizeTrapezoid) (pDst, traps, 0, 0);
			uxa_finish_access(pDraw);
		}
	} else if (maskFormat) {
		PicturePtr pPicture;
		INT16 xDst, yDst;
		INT16 xRel, yRel;
		int width, height;
		pixman_image_t *image;
		pixman_format_code_t format;

		xDst = traps[0].left.p1.x >> 16;
		yDst = traps[0].left.p1.y >> 16;

		width = bounds.x2 - bounds.x1;
		height = bounds.y2 - bounds.y1;

		format =
		    maskFormat->
		    format | (BitsPerPixel(maskFormat->depth) << 24);
		image =
		    pixman_image_create_bits(format, width, height, NULL, 0);
		if (!image)
			return;

		for (; ntrap; ntrap--, traps++)
			pixman_rasterize_trapezoid(image,
						   (pixman_trapezoid_t *) traps,
						   -bounds.x1, -bounds.y1);

		pPicture =
		    uxa_picture_from_pixman_image(pScreen, image, format);
		pixman_image_unref(image);
		if (!pPicture)
			return;

		xRel = bounds.x1 + xSrc - xDst;
		yRel = bounds.y1 + ySrc - yDst;
		CompositePicture(op, pSrc, pPicture, pDst,
				 xRel, yRel, 0, 0, bounds.x1, bounds.y1,
				 bounds.x2 - bounds.x1, bounds.y2 - bounds.y1);
		FreePicture(pPicture, 0);
	} else {
		if (pDst->polyEdge == PolyEdgeSharp)
			maskFormat = PictureMatchFormat(pScreen, 1, PICT_a1);
		else
			maskFormat = PictureMatchFormat(pScreen, 8, PICT_a8);
		for (; ntrap; ntrap--, traps++)
			uxa_trapezoids(op, pSrc, pDst, maskFormat, xSrc, ySrc,
				       1, traps);
	}
}

/**
 * uxa_triangles is essentially a copy of miTriangles that uses
 * uxa_create_alpha_picture instead of miCreateAlphaPicture.
 *
 * The problem with miCreateAlphaPicture is that it calls PolyFillRect
 * to initialize the contents after creating the pixmap, which
 * causes the pixmap to be moved in for acceleration. The subsequent
 * call to AddTriangles won't be accelerated however, which forces the pixmap
 * to be moved out again.
 *
 * uxa_create_alpha_picture avoids this roundtrip by using
 * uxa_check_poly_fill_rect to initialize the contents.
 */
void
uxa_triangles(CARD8 op, PicturePtr pSrc, PicturePtr pDst,
	      PictFormatPtr maskFormat, INT16 xSrc, INT16 ySrc,
	      int ntri, xTriangle * tris)
{
	ScreenPtr pScreen = pDst->pDrawable->pScreen;
	PictureScreenPtr ps = GetPictureScreen(pScreen);
	BoxRec bounds;
	Bool direct = op == PictOpAdd && miIsSolidAlpha(pSrc);

	if (maskFormat || direct) {
		miTriangleBounds(ntri, tris, &bounds);

		if (bounds.y1 >= bounds.y2 || bounds.x1 >= bounds.x2)
			return;
	}

	/*
	 * Check for solid alpha add
	 */
	if (direct) {
		DrawablePtr pDraw = pDst->pDrawable;
		if (uxa_prepare_access(pDraw, UXA_ACCESS_RW)) {
			(*ps->AddTriangles) (pDst, 0, 0, ntri, tris);
			uxa_finish_access(pDraw);
		}
	} else if (maskFormat) {
		PicturePtr pPicture;
		INT16 xDst, yDst;
		INT16 xRel, yRel;
		int width = bounds.x2 - bounds.x1;
		int height = bounds.y2 - bounds.y1;
		GCPtr pGC;
		xRectangle rect;

		xDst = tris[0].p1.x >> 16;
		yDst = tris[0].p1.y >> 16;

		pPicture = uxa_create_alpha_picture(pScreen, pDst, maskFormat,
						    width, height);
		if (!pPicture)
			return;

		/* Clear the alpha picture to 0. */
		pGC = GetScratchGC(pPicture->pDrawable->depth, pScreen);
		if (!pGC) {
			FreePicture(pPicture, 0);
			return;
		}
		ValidateGC(pPicture->pDrawable, pGC);
		rect.x = 0;
		rect.y = 0;
		rect.width = width;
		rect.height = height;
		uxa_check_poly_fill_rect(pPicture->pDrawable, pGC, 1, &rect);
		FreeScratchGC(pGC);

		if (uxa_prepare_access(pPicture->pDrawable, UXA_ACCESS_RW)) {
			(*ps->AddTriangles) (pPicture, -bounds.x1, -bounds.y1,
					     ntri, tris);
			uxa_finish_access(pPicture->pDrawable);
		}

		xRel = bounds.x1 + xSrc - xDst;
		yRel = bounds.y1 + ySrc - yDst;
		CompositePicture(op, pSrc, pPicture, pDst,
				 xRel, yRel, 0, 0, bounds.x1, bounds.y1,
				 bounds.x2 - bounds.x1, bounds.y2 - bounds.y1);
		FreePicture(pPicture, 0);
	} else {
		if (pDst->polyEdge == PolyEdgeSharp)
			maskFormat = PictureMatchFormat(pScreen, 1, PICT_a1);
		else
			maskFormat = PictureMatchFormat(pScreen, 8, PICT_a8);

		for (; ntri; ntri--, tris++)
			uxa_triangles(op, pSrc, pDst, maskFormat, xSrc, ySrc, 1,
				      tris);
	}
}