ReactOS 0.4.15-dev-8127-g6338913
alphablend.c
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1/*
2 * PROJECT: Win32 subsystem
3 * LICENSE: See COPYING in the top level directory
4 * FILE: win32ss/gdi/dib/alphablend.c
5 * PURPOSE: AlphaBlend implementation suitable for all bit depths
6 * PROGRAMMERS: Jérôme Gardou
7 */
8
9#include <win32k.h>
10
11#define NDEBUG
12#include <debug.h>
13
14typedef union
15{
17 struct
18 {
23 } col;
25
26static __inline UCHAR
28{
29 return (val > 255) ? 255 : (UCHAR)val;
30}
31
34 RECTL* SourceRect, CLIPOBJ* ClipRegion,
35 XLATEOBJ* ColorTranslation, BLENDOBJ* BlendObj)
36{
37 INT DstX, DstY, SrcX, SrcY;
39 register NICEPIXEL32 DstPixel32;
40 register NICEPIXEL32 SrcPixel32;
41 UCHAR Alpha, SrcBpp = BitsPerFormat(Source->iBitmapFormat);
42 EXLATEOBJ* pexlo;
43 EXLATEOBJ exloSrcRGB, exloDstRGB, exloRGBSrc;
45
46 DPRINT("DIB_16BPP_AlphaBlend: srcRect: (%d,%d)-(%d,%d), dstRect: (%d,%d)-(%d,%d)\n",
47 SourceRect->left, SourceRect->top, SourceRect->right, SourceRect->bottom,
48 DestRect->left, DestRect->top, DestRect->right, DestRect->bottom);
49
50 BlendFunc = BlendObj->BlendFunction;
52 {
53 DPRINT1("BlendOp != AC_SRC_OVER\n");
54 return FALSE;
55 }
56 if (BlendFunc.BlendFlags != 0)
57 {
58 DPRINT1("BlendFlags != 0\n");
59 return FALSE;
60 }
62 {
63 DPRINT1("Unsupported AlphaFormat (0x%x)\n", BlendFunc.AlphaFormat);
64 return FALSE;
65 }
66 if ((BlendFunc.AlphaFormat & AC_SRC_ALPHA) != 0 &&
67 SrcBpp != 32)
68 {
69 DPRINT1("Source bitmap must be 32bpp when AC_SRC_ALPHA is set\n");
70 return FALSE;
71 }
72
73 if (!ColorTranslation)
74 {
75 DPRINT1("ColorTranslation must not be NULL!\n");
76 return FALSE;
77 }
78
79 pexlo = CONTAINING_RECORD(ColorTranslation, EXLATEOBJ, xlo);
80 EXLATEOBJ_vInitialize(&exloSrcRGB, pexlo->ppalSrc, &gpalRGB, 0, 0, 0);
81 EXLATEOBJ_vInitialize(&exloDstRGB, pexlo->ppalDst, &gpalRGB, 0, 0, 0);
82 EXLATEOBJ_vInitialize(&exloRGBSrc, &gpalRGB, pexlo->ppalSrc, 0, 0, 0);
83
84 SrcY = SourceRect->top;
85 DstY = DestRect->top;
86 while ( DstY < DestRect->bottom )
87 {
88 SrcX = SourceRect->left;
89 DstX = DestRect->left;
90 while(DstX < DestRect->right)
91 {
92 SrcPixel32.ul = DIB_GetSource(Source, SrcX, SrcY, &exloSrcRGB.xlo);
93 SrcPixel32.col.red = (SrcPixel32.col.red * BlendFunc.SourceConstantAlpha) / 255;
94 SrcPixel32.col.green = (SrcPixel32.col.green * BlendFunc.SourceConstantAlpha) / 255;
95 SrcPixel32.col.blue = (SrcPixel32.col.blue * BlendFunc.SourceConstantAlpha) / 255;
96
97 Alpha = ((BlendFunc.AlphaFormat & AC_SRC_ALPHA) != 0) ?
98 (SrcPixel32.col.alpha * BlendFunc.SourceConstantAlpha) / 255 :
100
101 DstPixel32.ul = DIB_GetSource(Dest, DstX, DstY, &exloDstRGB.xlo);
102 DstPixel32.col.red = Clamp8((DstPixel32.col.red * (255 - Alpha)) / 255 + SrcPixel32.col.red) ;
103 DstPixel32.col.green = Clamp8((DstPixel32.col.green * (255 - Alpha)) / 255 + SrcPixel32.col.green) ;
104 DstPixel32.col.blue = Clamp8((DstPixel32.col.blue * (255 - Alpha)) / 255 + SrcPixel32.col.blue) ;
105 DstPixel32.ul = XLATEOBJ_iXlate(&exloRGBSrc.xlo, DstPixel32.ul);
106 pfnDibPutPixel(Dest, DstX, DstY, XLATEOBJ_iXlate(ColorTranslation, DstPixel32.ul));
107
108 DstX++;
109 SrcX = SourceRect->left + ((DstX-DestRect->left)*(SourceRect->right - SourceRect->left))
110 /(DestRect->right-DestRect->left);
111 }
112 DstY++;
113 SrcY = SourceRect->top + ((DstY-DestRect->top)*(SourceRect->bottom - SourceRect->top))
114 /(DestRect->bottom-DestRect->top);
115 }
116
117 EXLATEOBJ_vCleanup(&exloDstRGB);
118 EXLATEOBJ_vCleanup(&exloRGBSrc);
119 EXLATEOBJ_vCleanup(&exloSrcRGB);
120
121 return TRUE;
122}
123
unsigned char BOOLEAN
#define DPRINT1
Definition: precomp.h:8
#define TRUE
Definition: types.h:120
#define FALSE
Definition: types.h:117
static const BLENDFUNCTION BlendFunc
Definition: general.c:34
GLdouble GLdouble right
Definition: glext.h:10859
GLint GLint bottom
Definition: glext.h:7726
GLuint GLfloat * val
Definition: glext.h:7180
#define AC_SRC_ALPHA
Definition: alphablend.c:9
_In_ UINT _In_ UINT _In_ PNDIS_PACKET Source
Definition: ndis.h:3169
#define DPRINT
Definition: sndvol32.h:73
PFN_DIB_PutPixel DIB_PutPixel
Definition: dib.h:45
long bottom
Definition: polytest.cpp:53
long right
Definition: polytest.cpp:53
long top
Definition: polytest.cpp:53
long left
Definition: polytest.cpp:53
BYTE BlendOp
Definition: wingdi.h:2759
BYTE BlendFlags
Definition: wingdi.h:2760
BYTE AlphaFormat
Definition: wingdi.h:2762
BYTE SourceConstantAlpha
Definition: wingdi.h:2761
BLENDFUNCTION BlendFunction
Definition: winddi.h:224
XLATEOBJ xlo
Definition: xlateobj.h:21
PPALETTE ppalDst
Definition: xlateobj.h:26
PPALETTE ppalSrc
Definition: xlateobj.h:25
ULONG iBitmapFormat
Definition: winddi.h:1215
int32_t INT
Definition: typedefs.h:58
#define CONTAINING_RECORD(address, type, field)
Definition: typedefs.h:260
uint32_t ULONG
Definition: typedefs.h:59
UCHAR red
Definition: alphablend.c:19
UCHAR green
Definition: alphablend.c:20
UCHAR alpha
Definition: alphablend.c:22
struct NICEPIXEL32::@5083 col
ULONG ul
Definition: alphablend.c:16
UCHAR blue
Definition: alphablend.c:21
BOOLEAN DIB_XXBPP_AlphaBlend(SURFOBJ *Dest, SURFOBJ *Source, RECTL *DestRect, RECTL *SourceRect, CLIPOBJ *ClipRegion, XLATEOBJ *ColorTranslation, BLENDOBJ *BlendObj)
Definition: alphablend.c:33
static __inline UCHAR Clamp8(ULONG val)
Definition: alphablend.c:27
DIB_FUNCTIONS DibFunctionsForBitmapFormat[]
Definition: dib.c:20
#define DIB_GetSource(SourceSurf, sx, sy, ColorTranslation)
Definition: dib.h:136
VOID(* PFN_DIB_PutPixel)(SURFOBJ *, LONG, LONG, ULONG)
Definition: dib.h:33
#define BitsPerFormat(Format)
Definition: surface.h:109
PALETTE gpalRGB
Definition: palette.c:20
ENGAPI ULONG APIENTRY XLATEOBJ_iXlate(_In_ XLATEOBJ *pxlo, _In_ ULONG iColor)
Definition: xlateobj.c:664
#define AC_SRC_OVER
Definition: wingdi.h:1369
VOID NTAPI EXLATEOBJ_vInitialize(_Out_ PEXLATEOBJ pexlo, _In_opt_ PALETTE *ppalSrc, _In_opt_ PALETTE *ppalDst, _In_ COLORREF crSrcBackColor, _In_ COLORREF crDstBackColor, _In_ COLORREF crDstForeColor)
Definition: xlateobj.c:358
VOID NTAPI EXLATEOBJ_vCleanup(_Inout_ PEXLATEOBJ pexlo)
Definition: xlateobj.c:649
unsigned char UCHAR
Definition: xmlstorage.h:181