code.delx.au - refind/blob - libeg/image.c

   1 /*
   2  * libeg/image.c
   3  * Image handling functions
   4  *
   5  * Copyright (c) 2006 Christoph Pfisterer
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are
  10  * met:
  11  *
  12  *  * Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  *  * Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  *  * Neither the name of Christoph Pfisterer nor the names of the
  21  *    contributors may be used to endorse or promote products derived
  22  *    from this software without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  25  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  26  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  27  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  28  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  30  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  31  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  34  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 #include "libegint.h"
  38 #include "../refind/global.h"
  39 #include "../refind/lib.h"
  40 #include "../refind/screen.h"
  41 #include "../include/refit_call_wrapper.h"
  42 #include "lodepng.h"
  43
  44 #define MAX_FILE_SIZE (1024*1024*1024)
  45
  46 #ifndef __MAKEWITH_GNUEFI
  47 #define LibLocateHandle gBS->LocateHandleBuffer
  48 #define LibOpenRoot EfiLibOpenRoot
  49 #endif
  50
  51 //
  52 // Basic image handling
  53 //
  54
  55 EG_IMAGE * egCreateImage(IN UINTN Width, IN UINTN Height, IN BOOLEAN HasAlpha)
  56 {
  57     EG_IMAGE        *NewImage;
  58
  59     NewImage = (EG_IMAGE *) AllocatePool(sizeof(EG_IMAGE));
  60     if (NewImage == NULL)
  61         return NULL;
  62     NewImage->PixelData = (EG_PIXEL *) AllocatePool(Width * Height * sizeof(EG_PIXEL));
  63     if (NewImage->PixelData == NULL) {
  64         FreePool(NewImage);
  65         return NULL;
  66     }
  67
  68     NewImage->Width = Width;
  69     NewImage->Height = Height;
  70     NewImage->HasAlpha = HasAlpha;
  71     return NewImage;
  72 }
  73
  74 EG_IMAGE * egCreateFilledImage(IN UINTN Width, IN UINTN Height, IN BOOLEAN HasAlpha, IN EG_PIXEL *Color)
  75 {
  76     EG_IMAGE        *NewImage;
  77
  78     NewImage = egCreateImage(Width, Height, HasAlpha);
  79     if (NewImage == NULL)
  80         return NULL;
  81
  82     egFillImage(NewImage, Color);
  83     return NewImage;
  84 }
  85
  86 EG_IMAGE * egCopyImage(IN EG_IMAGE *Image)
  87 {
  88     EG_IMAGE        *NewImage = NULL;
  89
  90     if (Image != NULL)
  91        NewImage = egCreateImage(Image->Width, Image->Height, Image->HasAlpha);
  92     if (NewImage == NULL)
  93         return NULL;
  94
  95     CopyMem(NewImage->PixelData, Image->PixelData, Image->Width * Image->Height * sizeof(EG_PIXEL));
  96     return NewImage;
  97 }
  98
  99 // Returns a smaller image composed of the specified crop area from the larger area.
 100 // If the specified area is larger than is in the original, returns NULL.
 101 EG_IMAGE * egCropImage(IN EG_IMAGE *Image, IN UINTN StartX, IN UINTN StartY, IN UINTN Width, IN UINTN Height) {
 102    EG_IMAGE *NewImage = NULL;
 103    UINTN x, y;
 104
 105    if (((StartX + Width) > Image->Width) || ((StartY + Height) > Image->Height))
 106       return NULL;
 107
 108    NewImage = egCreateImage(Width, Height, Image->HasAlpha);
 109    if (NewImage == NULL)
 110       return NULL;
 111
 112    for (y = 0; y < Height; y++) {
 113       for (x = 0; x < Width; x++) {
 114          NewImage->PixelData[y * NewImage->Width + x] = Image->PixelData[(y + StartY) * Image->Width + x + StartX];
 115       }
 116    }
 117    return NewImage;
 118 } // EG_IMAGE * egCropImage()
 119
 120 VOID egFreeImage(IN EG_IMAGE *Image)
 121 {
 122     if (Image != NULL) {
 123         if (Image->PixelData != NULL)
 124             FreePool(Image->PixelData);
 125         FreePool(Image);
 126     }
 127 }
 128
 129 //
 130 // Basic file operations
 131 //
 132
 133 EFI_STATUS egLoadFile(IN EFI_FILE* BaseDir, IN CHAR16 *FileName, OUT UINT8 **FileData, OUT UINTN *FileDataLength)
 134 {
 135     EFI_STATUS          Status;
 136     EFI_FILE_HANDLE     FileHandle;
 137     EFI_FILE_INFO       *FileInfo;
 138     UINT64              ReadSize;
 139     UINTN               BufferSize;
 140     UINT8               *Buffer;
 141
 142     Status = refit_call5_wrapper(BaseDir->Open, BaseDir, &FileHandle, FileName, EFI_FILE_MODE_READ, 0);
 143     if (EFI_ERROR(Status)) {
 144         return Status;
 145     }
 146
 147     FileInfo = LibFileInfo(FileHandle);
 148     if (FileInfo == NULL) {
 149         refit_call1_wrapper(FileHandle->Close, FileHandle);
 150         return EFI_NOT_FOUND;
 151     }
 152     ReadSize = FileInfo->FileSize;
 153     if (ReadSize > MAX_FILE_SIZE)
 154         ReadSize = MAX_FILE_SIZE;
 155     FreePool(FileInfo);
 156
 157     BufferSize = (UINTN)ReadSize;   // was limited to 1 GB above, so this is safe
 158     Buffer = (UINT8 *) AllocatePool(BufferSize);
 159     if (Buffer == NULL) {
 160         refit_call1_wrapper(FileHandle->Close, FileHandle);
 161         return EFI_OUT_OF_RESOURCES;
 162     }
 163
 164     Status = refit_call3_wrapper(FileHandle->Read, FileHandle, &BufferSize, Buffer);
 165     refit_call1_wrapper(FileHandle->Close, FileHandle);
 166     if (EFI_ERROR(Status)) {
 167         FreePool(Buffer);
 168         return Status;
 169     }
 170
 171     *FileData = Buffer;
 172     *FileDataLength = BufferSize;
 173     return EFI_SUCCESS;
 174 }
 175
 176 static EFI_GUID ESPGuid = { 0xc12a7328, 0xf81f, 0x11d2, { 0xba, 0x4b, 0x00, 0xa0, 0xc9, 0x3e, 0xc9, 0x3b } };
 177
 178 EFI_STATUS egFindESP(OUT EFI_FILE_HANDLE *RootDir)
 179 {
 180     EFI_STATUS          Status;
 181     UINTN               HandleCount = 0;
 182     EFI_HANDLE          *Handles;
 183
 184     Status = LibLocateHandle(ByProtocol, &ESPGuid, NULL, &HandleCount, &Handles);
 185     if (!EFI_ERROR(Status) && HandleCount > 0) {
 186         *RootDir = LibOpenRoot(Handles[0]);
 187         if (*RootDir == NULL)
 188             Status = EFI_NOT_FOUND;
 189         FreePool(Handles);
 190     }
 191     return Status;
 192 }
 193
 194 EFI_STATUS egSaveFile(IN EFI_FILE* BaseDir OPTIONAL, IN CHAR16 *FileName,
 195                       IN UINT8 *FileData, IN UINTN FileDataLength)
 196 {
 197     EFI_STATUS          Status;
 198     EFI_FILE_HANDLE     FileHandle;
 199     UINTN               BufferSize;
 200
 201     if (BaseDir == NULL) {
 202         Status = egFindESP(&BaseDir);
 203         if (EFI_ERROR(Status))
 204             return Status;
 205     }
 206
 207     Status = refit_call5_wrapper(BaseDir->Open, BaseDir, &FileHandle, FileName,
 208                                  EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE | EFI_FILE_MODE_CREATE, 0);
 209     if (EFI_ERROR(Status))
 210         return Status;
 211
 212     BufferSize = FileDataLength;
 213     Status = refit_call3_wrapper(FileHandle->Write, FileHandle, &BufferSize, FileData);
 214     refit_call1_wrapper(FileHandle->Close, FileHandle);
 215
 216     return Status;
 217 }
 218
 219 //
 220 // Loading images from files and embedded data
 221 //
 222
 223 // Decode the specified image data. The IconSize parameter is relevant only
 224 // for ICNS, for which it selects which ICNS sub-image is decoded.
 225 // Returns a pointer to the resulting EG_IMAGE or NULL if decoding failed.
 226 static EG_IMAGE * egDecodeAny(IN UINT8 *FileData, IN UINTN FileDataLength, IN UINTN IconSize, IN BOOLEAN WantAlpha)
 227 {
 228    EG_IMAGE        *NewImage = NULL;
 229
 230    NewImage = egDecodeICNS(FileData, FileDataLength, IconSize, WantAlpha);
 231    if (NewImage == NULL)
 232       NewImage = egDecodePNG(FileData, FileDataLength, IconSize, WantAlpha);
 233    if (NewImage == NULL)
 234       NewImage = egDecodeBMP(FileData, FileDataLength, IconSize, WantAlpha);
 235
 236    return NewImage;
 237 }
 238
 239 EG_IMAGE * egLoadImage(IN EFI_FILE* BaseDir, IN CHAR16 *FileName, IN BOOLEAN WantAlpha)
 240 {
 241     EFI_STATUS      Status;
 242     UINT8           *FileData;
 243     UINTN           FileDataLength;
 244     EG_IMAGE        *NewImage;
 245
 246     if (BaseDir == NULL || FileName == NULL)
 247         return NULL;
 248
 249     // load file
 250     Status = egLoadFile(BaseDir, FileName, &FileData, &FileDataLength);
 251     if (EFI_ERROR(Status))
 252         return NULL;
 253
 254     // decode it
 255     NewImage = egDecodeAny(FileData, FileDataLength, 128, WantAlpha);
 256     FreePool(FileData);
 257
 258     return NewImage;
 259 }
 260
 261 // Load an icon from (BaseDir)/Path, extracting the icon of size IconSize x IconSize.
 262 // Returns a pointer to the image data, or NULL if the icon could not be loaded.
 263 EG_IMAGE * egLoadIcon(IN EFI_FILE* BaseDir, IN CHAR16 *Path, IN UINTN IconSize)
 264 {
 265     EFI_STATUS      Status;
 266     UINT8           *FileData;
 267     UINTN           FileDataLength;
 268     EG_IMAGE        *NewImage;
 269
 270     if (BaseDir == NULL || Path == NULL)
 271         return NULL;
 272
 273     // load file
 274     Status = egLoadFile(BaseDir, Path, &FileData, &FileDataLength);
 275     if (EFI_ERROR(Status))
 276        return NULL;
 277
 278     // decode it
 279     NewImage = egDecodeAny(FileData, FileDataLength, IconSize, TRUE);
 280     FreePool(FileData);
 281     if ((NewImage->Width != IconSize) || (NewImage->Height != IconSize)) {
 282        Print(L"Warning: Attempt to load icon of the wrong size from '%s'\n", Path);
 283        MyFreePool(NewImage);
 284        NewImage = NULL;
 285     }
 286
 287     return NewImage;
 288 } // EG_IMAGE *egLoadIcon()
 289
 290 // Returns an icon of any type from the specified subdirectory using the specified
 291 // base name. All directory references are relative to BaseDir. For instance, if
 292 // SubdirName is "myicons" and BaseName is "os_linux", this function will return
 293 // an image based on "myicons/os_linux.icns" or "myicons/os_linux.png", in that
 294 // order of preference. Returns NULL if no such file is a valid icon file.
 295 EG_IMAGE * egLoadIconAnyType(IN EFI_FILE *BaseDir, IN CHAR16 *SubdirName, IN CHAR16 *BaseName, IN UINTN IconSize) {
 296    EG_IMAGE *Image = NULL;
 297    CHAR16 *Extension;
 298    CHAR16 FileName[256];
 299    UINTN i = 0;
 300
 301    while (((Extension = FindCommaDelimited(ICON_EXTENSIONS, i++)) != NULL) && (Image == NULL)) {
 302       SPrint(FileName, 255, L"%s\\%s.%s", SubdirName, BaseName, Extension);
 303       Image = egLoadIcon(BaseDir, FileName, IconSize);
 304       MyFreePool(Extension);
 305    } // while()
 306
 307    return Image;
 308 } // EG_IMAGE *egLoadIconAnyType()
 309
 310 // Returns an icon with any extension in ICON_EXTENSIONS from either the directory
 311 // specified by GlobalConfig.IconsDir or DEFAULT_ICONS_DIR. The input BaseName
 312 // should be the icon name without an extension. For instance, if BaseName is
 313 // os_linux, GlobalConfig.IconsDir is myicons, DEFAULT_ICONS_DIR is icons, and
 314 // ICON_EXTENSIONS is "icns,png", this function will return myicons/os_linux.icns,
 315 // myicons/os_linux.png, icons/os_linux.icns, or icons/os_linux.png, in that
 316 // order of preference. Returns NULL if no such icon can be found. All file
 317 // references are relative to SelfDir.
 318 EG_IMAGE * egFindIcon(IN CHAR16 *BaseName, IN UINTN IconSize) {
 319    EG_IMAGE *Image = NULL;
 320
 321    if (GlobalConfig.IconsDir != NULL) {
 322       Image = egLoadIconAnyType(SelfDir, GlobalConfig.IconsDir, BaseName, IconSize);
 323    }
 324
 325    if (Image == NULL) {
 326       Image = egLoadIconAnyType(SelfDir, DEFAULT_ICONS_DIR, BaseName, IconSize);
 327    }
 328
 329    return Image;
 330 } // EG_IMAGE * egFindIcon()
 331
 332 EG_IMAGE * egPrepareEmbeddedImage(IN EG_EMBEDDED_IMAGE *EmbeddedImage, IN BOOLEAN WantAlpha)
 333 {
 334     EG_IMAGE            *NewImage;
 335     UINT8               *CompData;
 336     UINTN               CompLen;
 337     UINTN               PixelCount;
 338
 339     // sanity check
 340     if (EmbeddedImage->PixelMode > EG_MAX_EIPIXELMODE ||
 341         (EmbeddedImage->CompressMode != EG_EICOMPMODE_NONE && EmbeddedImage->CompressMode != EG_EICOMPMODE_RLE))
 342         return NULL;
 343
 344     // allocate image structure and pixel buffer
 345     NewImage = egCreateImage(EmbeddedImage->Width, EmbeddedImage->Height, WantAlpha);
 346     if (NewImage == NULL)
 347         return NULL;
 348
 349     CompData = (UINT8 *)EmbeddedImage->Data;   // drop const
 350     CompLen  = EmbeddedImage->DataLength;
 351     PixelCount = EmbeddedImage->Width * EmbeddedImage->Height;
 352
 353     // FUTURE: for EG_EICOMPMODE_EFICOMPRESS, decompress whole data block here
 354
 355     if (EmbeddedImage->PixelMode == EG_EIPIXELMODE_GRAY ||
 356         EmbeddedImage->PixelMode == EG_EIPIXELMODE_GRAY_ALPHA) {
 357
 358         // copy grayscale plane and expand
 359         if (EmbeddedImage->CompressMode == EG_EICOMPMODE_RLE) {
 360             egDecompressIcnsRLE(&CompData, &CompLen, PLPTR(NewImage, r), PixelCount);
 361         } else {
 362             egInsertPlane(CompData, PLPTR(NewImage, r), PixelCount);
 363             CompData += PixelCount;
 364         }
 365         egCopyPlane(PLPTR(NewImage, r), PLPTR(NewImage, g), PixelCount);
 366         egCopyPlane(PLPTR(NewImage, r), PLPTR(NewImage, b), PixelCount);
 367
 368     } else if (EmbeddedImage->PixelMode == EG_EIPIXELMODE_COLOR ||
 369                EmbeddedImage->PixelMode == EG_EIPIXELMODE_COLOR_ALPHA) {
 370
 371         // copy color planes
 372         if (EmbeddedImage->CompressMode == EG_EICOMPMODE_RLE) {
 373             egDecompressIcnsRLE(&CompData, &CompLen, PLPTR(NewImage, r), PixelCount);
 374             egDecompressIcnsRLE(&CompData, &CompLen, PLPTR(NewImage, g), PixelCount);
 375             egDecompressIcnsRLE(&CompData, &CompLen, PLPTR(NewImage, b), PixelCount);
 376         } else {
 377             egInsertPlane(CompData, PLPTR(NewImage, r), PixelCount);
 378             CompData += PixelCount;
 379             egInsertPlane(CompData, PLPTR(NewImage, g), PixelCount);
 380             CompData += PixelCount;
 381             egInsertPlane(CompData, PLPTR(NewImage, b), PixelCount);
 382             CompData += PixelCount;
 383         }
 384
 385     } else {
 386
 387         // set color planes to black
 388         egSetPlane(PLPTR(NewImage, r), 0, PixelCount);
 389         egSetPlane(PLPTR(NewImage, g), 0, PixelCount);
 390         egSetPlane(PLPTR(NewImage, b), 0, PixelCount);
 391
 392     }
 393
 394     if (WantAlpha && (EmbeddedImage->PixelMode == EG_EIPIXELMODE_GRAY_ALPHA ||
 395                       EmbeddedImage->PixelMode == EG_EIPIXELMODE_COLOR_ALPHA ||
 396                       EmbeddedImage->PixelMode == EG_EIPIXELMODE_ALPHA)) {
 397
 398         // copy alpha plane
 399         if (EmbeddedImage->CompressMode == EG_EICOMPMODE_RLE) {
 400             egDecompressIcnsRLE(&CompData, &CompLen, PLPTR(NewImage, a), PixelCount);
 401         } else {
 402             egInsertPlane(CompData, PLPTR(NewImage, a), PixelCount);
 403             CompData += PixelCount;
 404         }
 405
 406     } else {
 407         egSetPlane(PLPTR(NewImage, a), WantAlpha ? 255 : 0, PixelCount);
 408     }
 409
 410     return NewImage;
 411 }
 412
 413 //
 414 // Compositing
 415 //
 416
 417 VOID egRestrictImageArea(IN EG_IMAGE *Image,
 418                          IN UINTN AreaPosX, IN UINTN AreaPosY,
 419                          IN OUT UINTN *AreaWidth, IN OUT UINTN *AreaHeight)
 420 {
 421     if (AreaPosX >= Image->Width || AreaPosY >= Image->Height) {
 422         // out of bounds, operation has no effect
 423         *AreaWidth  = 0;
 424         *AreaHeight = 0;
 425     } else {
 426         // calculate affected area
 427         if (*AreaWidth > Image->Width - AreaPosX)
 428             *AreaWidth = Image->Width - AreaPosX;
 429         if (*AreaHeight > Image->Height - AreaPosY)
 430             *AreaHeight = Image->Height - AreaPosY;
 431     }
 432 }
 433
 434 VOID egFillImage(IN OUT EG_IMAGE *CompImage, IN EG_PIXEL *Color)
 435 {
 436     UINTN       i;
 437     EG_PIXEL    FillColor;
 438     EG_PIXEL    *PixelPtr;
 439
 440     FillColor = *Color;
 441     if (!CompImage->HasAlpha)
 442         FillColor.a = 0;
 443
 444     PixelPtr = CompImage->PixelData;
 445     for (i = 0; i < CompImage->Width * CompImage->Height; i++, PixelPtr++)
 446         *PixelPtr = FillColor;
 447 }
 448
 449 VOID egFillImageArea(IN OUT EG_IMAGE *CompImage,
 450                      IN UINTN AreaPosX, IN UINTN AreaPosY,
 451                      IN UINTN AreaWidth, IN UINTN AreaHeight,
 452                      IN EG_PIXEL *Color)
 453 {
 454     UINTN       x, y;
 455     EG_PIXEL    FillColor;
 456     EG_PIXEL    *PixelPtr;
 457     EG_PIXEL    *PixelBasePtr;
 458
 459     egRestrictImageArea(CompImage, AreaPosX, AreaPosY, &AreaWidth, &AreaHeight);
 460
 461     if (AreaWidth > 0) {
 462         FillColor = *Color;
 463         if (!CompImage->HasAlpha)
 464             FillColor.a = 0;
 465
 466         PixelBasePtr = CompImage->PixelData + AreaPosY * CompImage->Width + AreaPosX;
 467         for (y = 0; y < AreaHeight; y++) {
 468             PixelPtr = PixelBasePtr;
 469             for (x = 0; x < AreaWidth; x++, PixelPtr++)
 470                 *PixelPtr = FillColor;
 471             PixelBasePtr += CompImage->Width;
 472         }
 473     }
 474 }
 475
 476 VOID egRawCopy(IN OUT EG_PIXEL *CompBasePtr, IN EG_PIXEL *TopBasePtr,
 477                IN UINTN Width, IN UINTN Height,
 478                IN UINTN CompLineOffset, IN UINTN TopLineOffset)
 479 {
 480     UINTN       x, y;
 481     EG_PIXEL    *TopPtr, *CompPtr;
 482
 483     for (y = 0; y < Height; y++) {
 484         TopPtr = TopBasePtr;
 485         CompPtr = CompBasePtr;
 486         for (x = 0; x < Width; x++) {
 487             *CompPtr = *TopPtr;
 488             TopPtr++, CompPtr++;
 489         }
 490         TopBasePtr += TopLineOffset;
 491         CompBasePtr += CompLineOffset;
 492     }
 493 }
 494
 495 VOID egRawCompose(IN OUT EG_PIXEL *CompBasePtr, IN EG_PIXEL *TopBasePtr,
 496                   IN UINTN Width, IN UINTN Height,
 497                   IN UINTN CompLineOffset, IN UINTN TopLineOffset)
 498 {
 499     UINTN       x, y;
 500     EG_PIXEL    *TopPtr, *CompPtr;
 501     UINTN       Alpha;
 502     UINTN       RevAlpha;
 503     UINTN       Temp;
 504
 505     for (y = 0; y < Height; y++) {
 506         TopPtr = TopBasePtr;
 507         CompPtr = CompBasePtr;
 508         for (x = 0; x < Width; x++) {
 509             Alpha = TopPtr->a;
 510             RevAlpha = 255 - Alpha;
 511             Temp = (UINTN)CompPtr->b * RevAlpha + (UINTN)TopPtr->b * Alpha + 0x80;
 512             CompPtr->b = (Temp + (Temp >> 8)) >> 8;
 513             Temp = (UINTN)CompPtr->g * RevAlpha + (UINTN)TopPtr->g * Alpha + 0x80;
 514             CompPtr->g = (Temp + (Temp >> 8)) >> 8;
 515             Temp = (UINTN)CompPtr->r * RevAlpha + (UINTN)TopPtr->r * Alpha + 0x80;
 516             CompPtr->r = (Temp + (Temp >> 8)) >> 8;
 517             /*
 518             CompPtr->b = ((UINTN)CompPtr->b * RevAlpha + (UINTN)TopPtr->b * Alpha) / 255;
 519             CompPtr->g = ((UINTN)CompPtr->g * RevAlpha + (UINTN)TopPtr->g * Alpha) / 255;
 520             CompPtr->r = ((UINTN)CompPtr->r * RevAlpha + (UINTN)TopPtr->r * Alpha) / 255;
 521             */
 522             TopPtr++, CompPtr++;
 523         }
 524         TopBasePtr += TopLineOffset;
 525         CompBasePtr += CompLineOffset;
 526     }
 527 }
 528
 529 VOID egComposeImage(IN OUT EG_IMAGE *CompImage, IN EG_IMAGE *TopImage, IN UINTN PosX, IN UINTN PosY)
 530 {
 531     UINTN       CompWidth, CompHeight;
 532
 533     CompWidth  = TopImage->Width;
 534     CompHeight = TopImage->Height;
 535     egRestrictImageArea(CompImage, PosX, PosY, &CompWidth, &CompHeight);
 536
 537     // compose
 538     if (CompWidth > 0) {
 539         if (TopImage->HasAlpha) {
 540             egRawCompose(CompImage->PixelData + PosY * CompImage->Width + PosX, TopImage->PixelData,
 541                          CompWidth, CompHeight, CompImage->Width, TopImage->Width);
 542         } else {
 543             egRawCopy(CompImage->PixelData + PosY * CompImage->Width + PosX, TopImage->PixelData,
 544                       CompWidth, CompHeight, CompImage->Width, TopImage->Width);
 545         }
 546     }
 547 } /* VOID egComposeImage() */
 548
 549 EG_IMAGE * egEnsureImageSize(IN EG_IMAGE *Image, IN UINTN Width, IN UINTN Height, IN EG_PIXEL *Color)
 550 {
 551     EG_IMAGE *NewImage;
 552
 553     if (Image == NULL)
 554         return NULL;
 555     if (Image->Width == Width && Image->Height == Height)
 556         return Image;
 557
 558     NewImage = egCreateFilledImage(Width, Height, Image->HasAlpha, Color);
 559     if (NewImage == NULL) {
 560         egFreeImage(Image);
 561         return NULL;
 562     }
 563     Image->HasAlpha = FALSE;
 564     egComposeImage(NewImage, Image, 0, 0);
 565     egFreeImage(Image);
 566
 567     return NewImage;
 568 }
 569
 570 //
 571 // misc internal functions
 572 //
 573
 574 VOID egInsertPlane(IN UINT8 *SrcDataPtr, IN UINT8 *DestPlanePtr, IN UINTN PixelCount)
 575 {
 576     UINTN i;
 577
 578     for (i = 0; i < PixelCount; i++) {
 579         *DestPlanePtr = *SrcDataPtr++;
 580         DestPlanePtr += 4;
 581     }
 582 }
 583
 584 VOID egSetPlane(IN UINT8 *DestPlanePtr, IN UINT8 Value, IN UINTN PixelCount)
 585 {
 586     UINTN i;
 587
 588     for (i = 0; i < PixelCount; i++) {
 589         *DestPlanePtr = Value;
 590         DestPlanePtr += 4;
 591     }
 592 }
 593
 594 VOID egCopyPlane(IN UINT8 *SrcPlanePtr, IN UINT8 *DestPlanePtr, IN UINTN PixelCount)
 595 {
 596     UINTN i;
 597
 598     for (i = 0; i < PixelCount; i++) {
 599         *DestPlanePtr = *SrcPlanePtr;
 600         DestPlanePtr += 4, SrcPlanePtr += 4;
 601     }
 602 }
 603
 604 /* EOF */