/* * CiderPress * Copyright (C) 2007 by faddenSoft, LLC. All Rights Reserved. * See the file LICENSE for distribution terms. */ /* * DIB (Device-Independent Bitmap) wrapper. * * [ Ported back from libfadden -- there's a lot of stuff here that we don't * want or need, but it's easier to knock the bugs out if everybody is * using roughly the same code. ] */ #ifndef __LF_DIBITMAP__ #define __LF_DIBITMAP__ /* * Wraps a device-independent bitmap. * * When the bitmap is initially loaded, the object may or may not allocate a * DIB section in system memory. If the DIB handle is requested, a conversion * will be forced. This is done for efficiency in situations where the * bitmap isn't going to be handed off to GDI, or will only be used as a DDB. * * Some bitmaps have a transparent color (1-bit alpha) or a full alpha * channel. The behavior works like this: * - If the bitmap is <= 24 bits, alpha defaults to "off". * - If the bitmap is 32 bits, alpha defaults to "full". * - If the app calls SetAlphaColor, alpha is set to "transparency". * Calling GetPixelRGB returns a 32-bit value for which the alpha value * is always set. For "none" it's always 255, for "transparency" it's * either set to 0 or 255, and for "full" it's set to rgbReserved in a * 32-bit bitmap (or 255 for any other value). */ class MyDIBitmap { public: typedef enum AlphaType { kAlphaUnknown, kAlphaOpaque, // always stuff 255 into rgbReserved kAlphaTransparency, // single-bit alpha kAlphaFull // alpha channel in rgbReserved } AlphaType; enum { kAlphaMask = 0xff000000 }; // alpha byte in an ARGB DWORD MyDIBitmap(void) : mhBitmap(nil), mpFileBuffer(nil), mWidth(-1), mHeight(-1), mBpp(-1), mPitchBytes(0), mNumColorsUsed(0), mpColorTable(nil), mColorTableInitialized(false), mpPixels(nil), mAlphaType(kAlphaOpaque), mTransparentColor(0) { memset(&mBitmapInfoHdr, 0, sizeof(mBitmapInfoHdr)); } virtual ~MyDIBitmap(void); // create an empty bitmap with the specified characteristics; returns a // pointer to the pixel storage void* Create(int width, int height, int bitsPerPixel, int colorsUsed, bool dibSection = false); void SetColorTable(const RGBQUAD* pColorTable); const RGBQUAD* GetColorTable(void) const { return mpColorTable; } // zero out the pixels void ClearPixels(void); HBITMAP ConvertToDDB(HDC dc) const; // create a DIB from a file on disk int CreateFromFile(const char* fileName); int CreateFromFile(FILE* fp, long len); // create from memory buffer; set "doDelete" if object should own mem // (if "doDelete" is set, memory will be deleted if function fails) // contents of buffer will be analyzed to determine file type int CreateFromBuffer(void* buffer, long len, bool doDelete); // create a DIB from an embedded resource void* CreateFromResource(HINSTANCE hInstance, const char* rsrc); // write bitmap to file (for FILE*, make sure it's open in "wb" mode) int WriteToFile(const char* fileName) const; int WriteToFile(FILE* fp) const; // simple getters virtual int GetWidth(void) const { return mWidth; } virtual int GetHeight(void) const { return mHeight; } int GetBpp(void) const { return mBpp; } int GetNumColorsUsed(void) const { return mNumColorsUsed; } // retrieve current alpha mode AlphaType GetAlphaType(void) const { return mAlphaType; } // get transparent color; returns "false" if none has been set bool GetTransparentColor(RGBQUAD* pColor) const; // set transparent color and change alpha to kAlphaTransparency void SetTransparentColor(const RGBQUAD* pColor); // return the index of the specified color (-1 if not found, -2 on err) int LookupColor(const RGBQUAD* pRgbQuad); // set/get individual pixel values; the "RGB" functions always set // alpha to zero, while "RGBA" follow the current alpha mode void FASTCALL GetPixelRGB(int x, int y, RGBQUAD* pRgbQuad) const; void FASTCALL SetPixelRGB(int x, int y, const RGBQUAD* pRgbQuad); void FASTCALL GetPixelRGBA(int x, int y, RGBQUAD* pRgbQuad) const; void FASTCALL SetPixelRGBA(int x, int y, const RGBQUAD* pRgbQuad); void FASTCALL GetPixelIndex(int x, int y, int* pIdx) const; void FASTCALL SetPixelIndex(int x, int y, int idx); // Return a pointer to the raw pixel storage. void* GetPixelBuf(void) const { return mpPixels; } // Return the DIB handle; keep in mind that this HBITMAP is different // from a DDB HBITMAP, and many calls that take an HBITMAP will fail. HBITMAP GetHandle(void) { if (mhBitmap == nil && mpFileBuffer != nil) ConvertBufToDIBSection(); return mhBitmap; } int GetPitch(void) const { return mPitchBytes; } // Blit pixels from one bitmap to another. static bool Blit(MyDIBitmap* pDstBits, const RECT* pDstRect, const MyDIBitmap* pSrcBits, const RECT* pSrcRect); private: enum { kBMPMagic = 0x4d42 }; // "BM" /* for .TGA files; does not map directly to file */ typedef struct TargaHeader { unsigned char idLength; unsigned char colorMapType; unsigned char imageType; unsigned short colorMapOrigin; unsigned short colorMapLen; unsigned char colorMapEntryLen; unsigned short xOffset; unsigned short yOffset; unsigned short width; unsigned short height; unsigned char bitsPerPixel; unsigned char imageDescriptor; } TargaHeader; enum { kTargaHeaderLen = 18, kTargaUnmappedRGB = 2, // for imageType field }; int ImportBMP(void* vbuf, long len); int ImportTGA(void* vbuf, long len); int ConvertBufToDIBSection(void); int CreateFromNewBuffer(void* vbuf, long len); BITMAPINFOHEADER mBitmapInfoHdr; /* either mhBitmap or mpFileContents will be non-nil, but not both */ HBITMAP mhBitmap; // DIB section handle, not DDB void* mpFileBuffer; // buffer with contents of .BMP int mWidth; int mHeight; int mBpp; // #of bits per pixel int mPitchBytes; // memory line pitch, in bytes int mNumColorsUsed; RGBQUAD* mpColorTable; bool mColorTableInitialized; void* mpPixels; // points to system-allocated mem AlphaType mAlphaType; DWORD mTransparentColor; // for single-bit alpha bitmaps }; #endif /*__LF_DIBITMAP__*/