aboutsummaryrefslogtreecommitdiffstats
path: root/code/renderer/tr_image.c
diff options
context:
space:
mode:
Diffstat (limited to 'code/renderer/tr_image.c')
-rw-r--r--code/renderer/tr_image.c2448
1 files changed, 1 insertions, 2447 deletions
diff --git a/code/renderer/tr_image.c b/code/renderer/tr_image.c
index 37b91c2..5812228 100644
--- a/code/renderer/tr_image.c
+++ b/code/renderer/tr_image.c
@@ -33,13 +33,11 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#define JPEG_INTERNALS
#include "../jpeg-6/jpeglib.h"
-#include "../qcommon/puff.h"
-
+#include "tr_image_png.h"
static void LoadBMP( const char *name, byte **pic, int *width, int *height );
static void LoadTGA( const char *name, byte **pic, int *width, int *height );
static void LoadJPG( const char *name, byte **pic, int *width, int *height );
-static void LoadPNG( const char *name, byte **pic, int *width, int *height );
static byte s_intensitytable[256];
static unsigned char s_gammatable[256];
@@ -1931,2450 +1929,6 @@ int SaveJPGToBuffer( byte *buffer, int quality,
//===================================================================
-/*
-=================
-PNG LOADING
-=================
-*/
-
-/*
- * Quake 3 image format : RGBA
- */
-
-#define Q3IMAGE_BYTESPERPIXEL (4)
-
-/*
- * PNG specifications
- */
-
-/*
- * The first 8 Bytes of every PNG-File are a fixed signature
- * to identify the file as a PNG.
- */
-
-#define PNG_Signature "\x89\x50\x4E\x47\xD\xA\x1A\xA"
-#define PNG_Signature_Size (8)
-
-/*
- * After the signature diverse chunks follow.
- * A chunk consists of a header and if Length
- * is bigger than 0 a body and a CRC of the body follow.
- */
-
-struct PNG_ChunkHeader
-{
- uint32_t Length;
- uint32_t Type;
-};
-
-#define PNG_ChunkHeader_Size (8)
-
-typedef uint32_t PNG_ChunkCRC;
-
-#define PNG_ChunkCRC_Size (4)
-
-/*
- * We use the following ChunkTypes.
- * All others are ignored.
- */
-
-#define MAKE_CHUNKTYPE(a,b,c,d) (((a) << 24) | ((b) << 16) | ((c) << 8) | ((d)))
-
-#define PNG_ChunkType_IHDR MAKE_CHUNKTYPE('I', 'H', 'D', 'R')
-#define PNG_ChunkType_PLTE MAKE_CHUNKTYPE('P', 'L', 'T', 'E')
-#define PNG_ChunkType_IDAT MAKE_CHUNKTYPE('I', 'D', 'A', 'T')
-#define PNG_ChunkType_IEND MAKE_CHUNKTYPE('I', 'E', 'N', 'D')
-#define PNG_ChunkType_tRNS MAKE_CHUNKTYPE('t', 'R', 'N', 'S')
-
-/*
- * Per specification the first chunk after the signature SHALL be IHDR.
- */
-
-struct PNG_Chunk_IHDR
-{
- uint32_t Width;
- uint32_t Height;
- uint8_t BitDepth;
- uint8_t ColourType;
- uint8_t CompressionMethod;
- uint8_t FilterMethod;
- uint8_t InterlaceMethod;
-};
-
-#define PNG_Chunk_IHDR_Size (13)
-
-/*
- * ColourTypes
- */
-
-#define PNG_ColourType_Grey (0)
-#define PNG_ColourType_True (2)
-#define PNG_ColourType_Indexed (3)
-#define PNG_ColourType_GreyAlpha (4)
-#define PNG_ColourType_TrueAlpha (6)
-
-/*
- * number of colour components
- *
- * Grey : 1 grey
- * True : 1 R, 1 G, 1 B
- * Indexed : 1 index
- * GreyAlpha : 1 grey, 1 alpha
- * TrueAlpha : 1 R, 1 G, 1 B, 1 alpha
- */
-
-#define PNG_NumColourComponents_Grey (1)
-#define PNG_NumColourComponents_True (3)
-#define PNG_NumColourComponents_Indexed (1)
-#define PNG_NumColourComponents_GreyAlpha (2)
-#define PNG_NumColourComponents_TrueAlpha (4)
-
-/*
- * For the different ColourTypes
- * different BitDepths are specified.
- */
-
-#define PNG_BitDepth_1 ( 1)
-#define PNG_BitDepth_2 ( 2)
-#define PNG_BitDepth_4 ( 4)
-#define PNG_BitDepth_8 ( 8)
-#define PNG_BitDepth_16 (16)
-
-/*
- * Only one valid CompressionMethod is standardized.
- */
-
-#define PNG_CompressionMethod_0 (0)
-
-/*
- * Only one valid FilterMethod is currently standardized.
- */
-
-#define PNG_FilterMethod_0 (0)
-
-/*
- * This FilterMethod defines 5 FilterTypes
- */
-
-#define PNG_FilterType_None (0)
-#define PNG_FilterType_Sub (1)
-#define PNG_FilterType_Up (2)
-#define PNG_FilterType_Average (3)
-#define PNG_FilterType_Paeth (4)
-
-/*
- * Two InterlaceMethods are standardized :
- * 0 - NonInterlaced
- * 1 - Interlaced
- */
-
-#define PNG_InterlaceMethod_NonInterlaced (0)
-#define PNG_InterlaceMethod_Interlaced (1)
-
-/*
- * The Adam7 interlace method uses 7 passes.
- */
-
-#define PNG_Adam7_NumPasses (7)
-
-/*
- * The compressed data starts with a header ...
- */
-
-struct PNG_ZlibHeader
-{
- uint8_t CompressionMethod;
- uint8_t Flags;
-};
-
-#define PNG_ZlibHeader_Size (2)
-
-/*
- * ... and is followed by a check value
- */
-
-#define PNG_ZlibCheckValue_Size (4)
-
-/*
- * Some support functions for buffered files follow.
- */
-
-/*
- * buffered file representation
- */
-
-struct BufferedFile
-{
- byte *Buffer;
- int Length;
- byte *Ptr;
- int BytesLeft;
-};
-
-/*
- * Read a file into a buffer.
- */
-
-static struct BufferedFile *ReadBufferedFile(const char *name)
-{
- struct BufferedFile *BF;
-
- /*
- * input verification
- */
-
- if(!name)
- {
- return(NULL);
- }
-
- /*
- * Allocate control struct.
- */
-
- BF = ri.Malloc(sizeof(struct BufferedFile));
- if(!BF)
- {
- return(NULL);
- }
-
- /*
- * Initialize the structs components.
- */
-
- BF->Length = 0;
- BF->Buffer = NULL;
- BF->Ptr = NULL;
- BF->BytesLeft = 0;
-
- /*
- * Read the file.
- */
-
- BF->Length = ri.FS_ReadFile((char *) name, (void **) &BF->Buffer);
-
- /*
- * Did we get it? Is it big enough?
- */
-
- if(!(BF->Buffer && (BF->Length > 0)))
- {
- ri.Free(BF);
-
- return(NULL);
- }
-
- /*
- * Set the pointers and counters.
- */
-
- BF->Ptr = BF->Buffer;
- BF->BytesLeft = BF->Length;
-
- return(BF);
-}
-
-/*
- * Close a buffered file.
- */
-
-static void CloseBufferedFile(struct BufferedFile *BF)
-{
- if(BF)
- {
- if(BF->Buffer)
- {
- ri.FS_FreeFile(BF->Buffer);
- }
-
- ri.Free(BF);
- }
-}
-
-/*
- * Get a pointer to the requested bytes.
- */
-
-static void *BufferedFileRead(struct BufferedFile *BF, int Length)
-{
- void *RetVal;
-
- /*
- * input verification
- */
-
- if(!(BF && Length))
- {
- return(NULL);
- }
-
- /*
- * not enough bytes left
- */
-
- if(Length > BF->BytesLeft)
- {
- return(NULL);
- }
-
- /*
- * the pointer to the requested data
- */
-
- RetVal = BF->Ptr;
-
- /*
- * Raise the pointer and counter.
- */
-
- BF->Ptr += Length;
- BF->BytesLeft -= Length;
-
- return(RetVal);
-}
-
-/*
- * Rewind the buffer.
- */
-
-static qboolean BufferedFileRewind(struct BufferedFile *BF, int Offset)
-{
- int BytesRead;
-
- /*
- * input verification
- */
-
- if(!BF)
- {
- return(qfalse);
- }
-
- /*
- * special trick to rewind to the beginning of the buffer
- */
-
- if(Offset == -1)
- {
- BF->Ptr = BF->Buffer;
- BF->BytesLeft = BF->Length;
-
- return(qtrue);
- }
-
- /*
- * How many bytes do we have already read?
- */
-
- BytesRead = BF->Ptr - BF->Buffer;
-
- /*
- * We can only rewind to the beginning of the BufferedFile.
- */
-
- if(Offset > BytesRead)
- {
- return(qfalse);
- }
-
- /*
- * lower the pointer and counter.
- */
-
- BF->Ptr -= Offset;
- BF->BytesLeft += Offset;
-
- return(qtrue);
-}
-
-/*
- * Skip some bytes.
- */
-
-static qboolean BufferedFileSkip(struct BufferedFile *BF, int Offset)
-{
- /*
- * input verification
- */
-
- if(!BF)
- {
- return(qfalse);
- }
-
- /*
- * We can only skip to the end of the BufferedFile.
- */
-
- if(Offset > BF->BytesLeft)
- {
- return(qfalse);
- }
-
- /*
- * lower the pointer and counter.
- */
-
- BF->Ptr += Offset;
- BF->BytesLeft -= Offset;
-
- return(qtrue);
-}
-
-/*
- * Find a chunk
- */
-
-static qboolean FindChunk(struct BufferedFile *BF, uint32_t ChunkType)
-{
- struct PNG_ChunkHeader *CH;
-
- uint32_t Length;
- uint32_t Type;
-
- /*
- * input verification
- */
-
- if(!BF)
- {
- return(qfalse);
- }
-
- /*
- * cycle trough the chunks
- */
-
- while(qtrue)
- {
- /*
- * Read the chunk-header.
- */
-
- CH = BufferedFileRead(BF, PNG_ChunkHeader_Size);
- if(!CH)
- {
- return(qfalse);
- }
-
- /*
- * Do not swap the original types
- * they might be needed later.
- */
-
- Length = BigLong(CH->Length);
- Type = BigLong(CH->Type);
-
- /*
- * We found it!
- */
-
- if(Type == ChunkType)
- {
- /*
- * Rewind to the start of the chunk.
- */
-
- BufferedFileRewind(BF, PNG_ChunkHeader_Size);
-
- break;
- }
- else
- {
- /*
- * Skip the rest of the chunk.
- */
-
- if(Length)
- {
- if(!BufferedFileSkip(BF, Length + PNG_ChunkCRC_Size))
- {
- return(qfalse);
- }
- }
- }
- }
-
- return(qtrue);
-}
-
-/*
- * Decompress all IDATs
- */
-
-static uint32_t DecompressIDATs(struct BufferedFile *BF, uint8_t **Buffer)
-{
- uint8_t *DecompressedData;
- uint32_t DecompressedDataLength;
-
- uint8_t *CompressedData;
- uint8_t *CompressedDataPtr;
- uint32_t CompressedDataLength;
-
- struct PNG_ChunkHeader *CH;
-
- uint32_t Length;
- uint32_t Type;
-
- int BytesToRewind;
-
- int32_t puffResult;
- uint8_t *puffDest;
- uint32_t puffDestLen;
- uint8_t *puffSrc;
- uint32_t puffSrcLen;
-
- /*
- * input verification
- */
-
- if(!(BF && Buffer))
- {
- return(-1);
- }
-
- /*
- * some zeroing
- */
-
- DecompressedData = NULL;
- DecompressedDataLength = 0;
- *Buffer = DecompressedData;
-
- CompressedData = NULL;
- CompressedDataLength = 0;
-
- BytesToRewind = 0;
-
- /*
- * Find the first IDAT chunk.
- */
-
- if(!FindChunk(BF, PNG_ChunkType_IDAT))
- {
- return(-1);
- }
-
- /*
- * Count the size of the uncompressed data
- */
-
- while(qtrue)
- {
- /*
- * Read chunk header
- */
-
- CH = BufferedFileRead(BF, PNG_ChunkHeader_Size);
- if(!CH)
- {
- /*
- * Rewind to the start of this adventure
- * and return unsuccessfull
- */
-
- BufferedFileRewind(BF, BytesToRewind);
-
- return(-1);
- }
-
- /*
- * Length and Type of chunk
- */
-
- Length = BigLong(CH->Length);
- Type = BigLong(CH->Type);
-
- /*
- * We have reached the end of the IDAT chunks
- */
-
- if(!(Type == PNG_ChunkType_IDAT))
- {
- BufferedFileRewind(BF, PNG_ChunkHeader_Size);
-
- break;
- }
-
- /*
- * Add chunk header to count.
- */
-
- BytesToRewind += PNG_ChunkHeader_Size;
-
- /*
- * Skip to next chunk
- */
-
- if(Length)
- {
- if(!BufferedFileSkip(BF, Length + PNG_ChunkCRC_Size))
- {
- BufferedFileRewind(BF, BytesToRewind);
-
- return(-1);
- }
-
- BytesToRewind += Length + PNG_ChunkCRC_Size;
- CompressedDataLength += Length;
- }
- }
-
- BufferedFileRewind(BF, BytesToRewind);
-
- CompressedData = ri.Malloc(CompressedDataLength);
- if(!CompressedData)
- {
- return(-1);
- }
-
- CompressedDataPtr = CompressedData;
-
- /*
- * Collect the compressed Data
- */
-
- while(qtrue)
- {
- /*
- * Read chunk header
- */
-
- CH = BufferedFileRead(BF, PNG_ChunkHeader_Size);
- if(!CH)
- {
- ri.Free(CompressedData);
-
- return(-1);
- }
-
- /*
- * Length and Type of chunk
- */
-
- Length = BigLong(CH->Length);
- Type = BigLong(CH->Type);
-
- /*
- * We have reached the end of the IDAT chunks
- */
-
- if(!(Type == PNG_ChunkType_IDAT))
- {
- BufferedFileRewind(BF, PNG_ChunkHeader_Size);
-
- break;
- }
-
- /*
- * Copy the Data
- */
-
- if(Length)
- {
- uint8_t *OrigCompressedData;
-
- OrigCompressedData = BufferedFileRead(BF, Length);
- if(!OrigCompressedData)
- {
- ri.Free(CompressedData);
-
- return(-1);
- }
-
- if(!BufferedFileSkip(BF, PNG_ChunkCRC_Size))
- {
- ri.Free(CompressedData);
-
- return(-1);
- }
-
- memcpy(CompressedDataPtr, OrigCompressedData, Length);
- CompressedDataPtr += Length;
- }
- }
-
- /*
- * Let puff() calculate the decompressed data length.
- */
-
- puffDest = NULL;
- puffDestLen = 0;
-
- /*
- * The zlib header and checkvalue don't belong to the compressed data.
- */
-
- puffSrc = CompressedData + PNG_ZlibHeader_Size;
- puffSrcLen = CompressedDataLength - PNG_ZlibHeader_Size - PNG_ZlibCheckValue_Size;
-
- /*
- * first puff() to calculate the size of the uncompressed data
- */
-
- puffResult = puff(puffDest, &puffDestLen, puffSrc, &puffSrcLen);
- if(!((puffResult == 0) && (puffDestLen > 0)))
- {
- ri.Free(CompressedData);
-
- return(-1);
- }
-
- /*
- * Allocate the buffer for the uncompressed data.
- */
-
- DecompressedData = ri.Malloc(puffDestLen);
- if(!DecompressedData)
- {
- ri.Free(CompressedData);
-
- return(-1);
- }
-
- /*
- * Set the input again in case something was changed by the last puff() .
- */
-
- puffDest = DecompressedData;
- puffSrc = CompressedData + PNG_ZlibHeader_Size;
- puffSrcLen = CompressedDataLength - PNG_ZlibHeader_Size - PNG_ZlibCheckValue_Size;
-
- /*
- * decompression puff()
- */
-
- puffResult = puff(puffDest, &puffDestLen, puffSrc, &puffSrcLen);
-
- /*
- * The compressed data is not needed anymore.
- */
-
- ri.Free(CompressedData);
-
- /*
- * Check if the last puff() was successfull.
- */
-
- if(!((puffResult == 0) && (puffDestLen > 0)))
- {
- ri.Free(DecompressedData);
-
- return(-1);
- }
-
- /*
- * Set the output of this function.
- */
-
- DecompressedDataLength = puffDestLen;
- *Buffer = DecompressedData;
-
- return(DecompressedDataLength);
-}
-
-/*
- * the Paeth predictor
- */
-
-static uint8_t PredictPaeth(uint8_t a, uint8_t b, uint8_t c)
-{
- /*
- * a == Left
- * b == Up
- * c == UpLeft
- */
-
- uint8_t Pr;
- int p;
- int pa, pb, pc;
-
- Pr = 0;
-
- p = ((int) a) + ((int) b) - ((int) c);
- pa = abs(p - ((int) a));
- pb = abs(p - ((int) b));
- pc = abs(p - ((int) c));
-
- if((pa <= pb) && (pa <= pc))
- {
- Pr = a;
- }
- else if(pb <= pc)
- {
- Pr = b;
- }
- else
- {
- Pr = c;
- }
-
- return(Pr);
-
-}
-
-/*
- * Reverse the filters.
- */
-
-static qboolean UnfilterImage(uint8_t *DecompressedData,
- uint32_t ImageHeight,
- uint32_t BytesPerScanline,
- uint32_t BytesPerPixel)
-{
- uint8_t *DecompPtr;
- uint8_t FilterType;
- uint8_t *PixelLeft, *PixelUp, *PixelUpLeft;
- uint32_t w, h, p;
-
- /*
- * some zeros for the filters
- */
-
- uint8_t Zeros[8] = {0, 0, 0, 0, 0, 0, 0, 0};
-
- /*
- * input verification
- *
- * ImageHeight and BytesPerScanline are not checked,
- * because these can be zero in some interlace passes.
- */
-
- if(!(DecompressedData && BytesPerPixel))
- {
- return(qfalse);
- }
-
-
- /*
- * Set the pointer to the start of the decompressed Data.
- */
-
- DecompPtr = DecompressedData;
-
- /*
- * Un-filtering is done in place.
- */
-
- /*
- * Go trough all scanlines.
- */
-
- for(h = 0; h < ImageHeight; h++)
- {
- /*
- * Every scanline starts with a FilterType byte.
- */
-
- FilterType = *DecompPtr;
- DecompPtr++;
-
- /*
- * Left pixel of the first byte in a scanline is zero.
- */
-
- PixelLeft = Zeros;
-
- /*
- * Set PixelUp to previous line only if we are on the second line or above.
- *
- * Plus one byte for the FilterType
- */
-
- if(h > 0)
- {
- PixelUp = DecompPtr - (BytesPerScanline + 1);
- }
- else
- {
- PixelUp = Zeros;
- }
-
- /*
- * The pixel left to the first pixel of the previous scanline is zero too.
- */
-
- PixelUpLeft = Zeros;
-
- /*
- * Cycle trough all pixels of the scanline.
- */
-
- for(w = 0; w < (BytesPerScanline / BytesPerPixel); w++)
- {
- /*
- * Cycle trough the bytes of the pixel.
- */
-
- for(p = 0; p < BytesPerPixel; p++)
- {
- switch(FilterType)
- {
- case PNG_FilterType_None :
- {
- /*
- * The byte is unfiltered.
- */
-
- break;
- }
-
- case PNG_FilterType_Sub :
- {
- DecompPtr[p] += PixelLeft[p];
-
- break;
- }
-
- case PNG_FilterType_Up :
- {
- DecompPtr[p] += PixelUp[p];
-
- break;
- }
-
- case PNG_FilterType_Average :
- {
- DecompPtr[p] += ((uint8_t) ((((uint16_t) PixelLeft[p]) + ((uint16_t) PixelUp[p])) / 2));
-
- break;
- }
-
- case PNG_FilterType_Paeth :
- {
- DecompPtr[p] += PredictPaeth(PixelLeft[p], PixelUp[p], PixelUpLeft[p]);
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
- }
-
- PixelLeft = DecompPtr;
-
- /*
- * We only have a upleft pixel if we are on the second line or above.
- */
-
- if(h > 0)
- {
- PixelUpLeft = DecompPtr - (BytesPerScanline + 1);
- }
-
- /*
- * Skip to the next pixel.
- */
-
- DecompPtr += BytesPerPixel;
-
- /*
- * We only have a previous line if we are on the second line and above.
- */
-
- if(h > 0)
- {
- PixelUp = DecompPtr - (BytesPerScanline + 1);
- }
- }
- }
-
- return(qtrue);
-}
-
-/*
- * Convert a raw input pixel to Quake 3 RGA format.
- */
-
-static qboolean ConvertPixel(struct PNG_Chunk_IHDR *IHDR,
- byte *OutPtr,
- uint8_t *DecompPtr,
- qboolean HasTransparentColour,
- uint8_t *TransparentColour,
- uint8_t *OutPal)
-{
- /*
- * input verification
- */
-
- if(!(IHDR && OutPtr && DecompPtr && TransparentColour && OutPal))
- {
- return(qfalse);
- }
-
- switch(IHDR->ColourType)
- {
- case PNG_ColourType_Grey :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_1 :
- case PNG_BitDepth_2 :
- case PNG_BitDepth_4 :
- {
- uint8_t Step;
- uint8_t GreyValue;
-
- Step = 0xFF / ((1 << IHDR->BitDepth) - 1);
-
- GreyValue = DecompPtr[0] * Step;
-
- OutPtr[0] = GreyValue;
- OutPtr[1] = GreyValue;
- OutPtr[2] = GreyValue;
- OutPtr[3] = 0xFF;
-
- /*
- * Grey supports full transparency for one specified colour
- */
-
- if(HasTransparentColour)
- {
- if(TransparentColour[1] == DecompPtr[0])
- {
- OutPtr[3] = 0x00;
- }
- }
-
-
- break;
- }
-
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[0];
- OutPtr[2] = DecompPtr[0];
- OutPtr[3] = 0xFF;
-
- /*
- * Grey supports full transparency for one specified colour
- */
-
- if(HasTransparentColour)
- {
- if(IHDR->BitDepth == PNG_BitDepth_8)
- {
- if(TransparentColour[1] == DecompPtr[0])
- {
- OutPtr[3] = 0x00;
- }
- }
- else
- {
- if((TransparentColour[0] == DecompPtr[0]) && (TransparentColour[1] == DecompPtr[1]))
- {
- OutPtr[3] = 0x00;
- }
- }
- }
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_True :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- {
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[1];
- OutPtr[2] = DecompPtr[2];
- OutPtr[3] = 0xFF;
-
- /*
- * True supports full transparency for one specified colour
- */
-
- if(HasTransparentColour)
- {
- if((TransparentColour[1] == DecompPtr[0]) &&
- (TransparentColour[3] == DecompPtr[1]) &&
- (TransparentColour[5] == DecompPtr[3]))
- {
- OutPtr[3] = 0x00;
- }
- }
-
- break;
- }
-
- case PNG_BitDepth_16 :
- {
- /*
- * We use only the upper byte.
- */
-
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[2];
- OutPtr[2] = DecompPtr[4];
- OutPtr[3] = 0xFF;
-
- /*
- * True supports full transparency for one specified colour
- */
-
- if(HasTransparentColour)
- {
- if((TransparentColour[0] == DecompPtr[0]) && (TransparentColour[1] == DecompPtr[1]) &&
- (TransparentColour[2] == DecompPtr[2]) && (TransparentColour[3] == DecompPtr[3]) &&
- (TransparentColour[4] == DecompPtr[4]) && (TransparentColour[5] == DecompPtr[5]))
- {
- OutPtr[3] = 0x00;
- }
- }
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_Indexed :
- {
- OutPtr[0] = OutPal[DecompPtr[0] * Q3IMAGE_BYTESPERPIXEL + 0];
- OutPtr[1] = OutPal[DecompPtr[0] * Q3IMAGE_BYTESPERPIXEL + 1];
- OutPtr[2] = OutPal[DecompPtr[0] * Q3IMAGE_BYTESPERPIXEL + 2];
- OutPtr[3] = OutPal[DecompPtr[0] * Q3IMAGE_BYTESPERPIXEL + 3];
-
- break;
- }
-
- case PNG_ColourType_GreyAlpha :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- {
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[0];
- OutPtr[2] = DecompPtr[0];
- OutPtr[3] = DecompPtr[1];
-
- break;
- }
-
- case PNG_BitDepth_16 :
- {
- /*
- * We use only the upper byte.
- */
-
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[0];
- OutPtr[2] = DecompPtr[0];
- OutPtr[3] = DecompPtr[2];
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_TrueAlpha :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- {
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[1];
- OutPtr[2] = DecompPtr[2];
- OutPtr[3] = DecompPtr[3];
-
- break;
- }
-
- case PNG_BitDepth_16 :
- {
- /*
- * We use only the upper byte.
- */
-
- OutPtr[0] = DecompPtr[0];
- OutPtr[1] = DecompPtr[2];
- OutPtr[2] = DecompPtr[4];
- OutPtr[3] = DecompPtr[6];
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- return(qtrue);
-}
-
-
-/*
- * Decode a non-interlaced image.
- */
-
-static qboolean DecodeImageNonInterlaced(struct PNG_Chunk_IHDR *IHDR,
- byte *OutBuffer,
- uint8_t *DecompressedData,
- uint32_t DecompressedDataLength,
- qboolean HasTransparentColour,
- uint8_t *TransparentColour,
- uint8_t *OutPal)
-{
- uint32_t IHDR_Width;
- uint32_t IHDR_Height;
- uint32_t BytesPerScanline, BytesPerPixel, PixelsPerByte;
- uint32_t w, h, p;
- byte *OutPtr;
- uint8_t *DecompPtr;
-
- /*
- * input verification
- */
-
- if(!(IHDR && OutBuffer && DecompressedData && DecompressedDataLength && TransparentColour && OutPal))
- {
- return(qfalse);
- }
-
- /*
- * byte swapping
- */
-
- IHDR_Width = BigLong(IHDR->Width);
- IHDR_Height = BigLong(IHDR->Height);
-
- /*
- * information for un-filtering
- */
-
- switch(IHDR->ColourType)
- {
- case PNG_ColourType_Grey :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_1 :
- case PNG_BitDepth_2 :
- case PNG_BitDepth_4 :
- {
- BytesPerPixel = 1;
- PixelsPerByte = 8 / IHDR->BitDepth;
-
- break;
- }
-
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_Grey;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_True :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_True;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_Indexed :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_1 :
- case PNG_BitDepth_2 :
- case PNG_BitDepth_4 :
- {
- BytesPerPixel = 1;
- PixelsPerByte = 8 / IHDR->BitDepth;
-
- break;
- }
-
- case PNG_BitDepth_8 :
- {
- BytesPerPixel = PNG_NumColourComponents_Indexed;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_GreyAlpha :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_GreyAlpha;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_TrueAlpha :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_TrueAlpha;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- /*
- * Calculate the size of one scanline
- */
-
- BytesPerScanline = (IHDR_Width * BytesPerPixel + (PixelsPerByte - 1)) / PixelsPerByte;
-
- /*
- * Check if we have enough data for the whole image.
- */
-
- if(!(DecompressedDataLength == ((BytesPerScanline + 1) * IHDR_Height)))
- {
- return(qfalse);
- }
-
- /*
- * Unfilter the image.
- */
-
- if(!UnfilterImage(DecompressedData, IHDR_Height, BytesPerScanline, BytesPerPixel))
- {
- return(qfalse);
- }
-
- /*
- * Set the working pointers to the beginning of the buffers.
- */
-
- OutPtr = OutBuffer;
- DecompPtr = DecompressedData;
-
- /*
- * Create the output image.
- */
-
- for(h = 0; h < IHDR_Height; h++)
- {
- /*
- * Count the pixels on the scanline for those multipixel bytes
- */
-
- uint32_t CurrPixel;
-
- /*
- * skip FilterType
- */
-
- DecompPtr++;
-
- /*
- * Reset the pixel count.
- */
-
- CurrPixel = 0;
-
- for(w = 0; w < (BytesPerScanline / BytesPerPixel); w++)
- {
- if(PixelsPerByte > 1)
- {
- uint8_t Mask;
- uint32_t Shift;
- uint8_t SinglePixel;
-
- for(p = 0; p < PixelsPerByte; p++)
- {
- if(CurrPixel < IHDR_Width)
- {
- Mask = (1 << IHDR->BitDepth) - 1;
- Shift = (PixelsPerByte - 1 - p) * IHDR->BitDepth;
-
- SinglePixel = ((DecompPtr[0] & (Mask << Shift)) >> Shift);
-
- if(!ConvertPixel(IHDR, OutPtr, &SinglePixel, HasTransparentColour, TransparentColour, OutPal))
- {
- return(qfalse);
- }
-
- OutPtr += Q3IMAGE_BYTESPERPIXEL;
- CurrPixel++;
- }
- }
-
- }
- else
- {
- if(!ConvertPixel(IHDR, OutPtr, DecompPtr, HasTransparentColour, TransparentColour, OutPal))
- {
- return(qfalse);
- }
-
-
- OutPtr += Q3IMAGE_BYTESPERPIXEL;
- }
-
- DecompPtr += BytesPerPixel;
- }
- }
-
- return(qtrue);
-}
-
-/*
- * Decode an interlaced image.
- */
-
-static qboolean DecodeImageInterlaced(struct PNG_Chunk_IHDR *IHDR,
- byte *OutBuffer,
- uint8_t *DecompressedData,
- uint32_t DecompressedDataLength,
- qboolean HasTransparentColour,
- uint8_t *TransparentColour,
- uint8_t *OutPal)
-{
- uint32_t IHDR_Width;
- uint32_t IHDR_Height;
- uint32_t BytesPerScanline[PNG_Adam7_NumPasses], BytesPerPixel, PixelsPerByte;
- uint32_t PassWidth[PNG_Adam7_NumPasses], PassHeight[PNG_Adam7_NumPasses];
- uint32_t WSkip[PNG_Adam7_NumPasses], WOffset[PNG_Adam7_NumPasses], HSkip[PNG_Adam7_NumPasses], HOffset[PNG_Adam7_NumPasses];
- uint32_t w, h, p, a;
- byte *OutPtr;
- uint8_t *DecompPtr;
- uint32_t TargetLength;
-
- /*
- * input verification
- */
-
- if(!(IHDR && OutBuffer && DecompressedData && DecompressedDataLength && TransparentColour && OutPal))
- {
- return(qfalse);
- }
-
- /*
- * byte swapping
- */
-
- IHDR_Width = BigLong(IHDR->Width);
- IHDR_Height = BigLong(IHDR->Height);
-
- /*
- * Skip and Offset for the passes.
- */
-
- WSkip[0] = 8;
- WOffset[0] = 0;
- HSkip[0] = 8;
- HOffset[0] = 0;
-
- WSkip[1] = 8;
- WOffset[1] = 4;
- HSkip[1] = 8;
- HOffset[1] = 0;
-
- WSkip[2] = 4;
- WOffset[2] = 0;
- HSkip[2] = 8;
- HOffset[2] = 4;
-
- WSkip[3] = 4;
- WOffset[3] = 2;
- HSkip[3] = 4;
- HOffset[3] = 0;
-
- WSkip[4] = 2;
- WOffset[4] = 0;
- HSkip[4] = 4;
- HOffset[4] = 2;
-
- WSkip[5] = 2;
- WOffset[5] = 1;
- HSkip[5] = 2;
- HOffset[5] = 0;
-
- WSkip[6] = 1;
- WOffset[6] = 0;
- HSkip[6] = 2;
- HOffset[6] = 1;
-
- /*
- * Calculate the sizes of the passes.
- */
-
- PassWidth[0] = (IHDR_Width + 7) / 8;
- PassHeight[0] = (IHDR_Height + 7) / 8;
-
- PassWidth[1] = (IHDR_Width + 3) / 8;
- PassHeight[1] = (IHDR_Height + 7) / 8;
-
- PassWidth[2] = (IHDR_Width + 3) / 4;
- PassHeight[2] = (IHDR_Height + 3) / 8;
-
- PassWidth[3] = (IHDR_Width + 1) / 4;
- PassHeight[3] = (IHDR_Height + 3) / 4;
-
- PassWidth[4] = (IHDR_Width + 1) / 2;
- PassHeight[4] = (IHDR_Height + 1) / 4;
-
- PassWidth[5] = (IHDR_Width + 0) / 2;
- PassHeight[5] = (IHDR_Height + 1) / 2;
-
- PassWidth[6] = (IHDR_Width + 0) / 1;
- PassHeight[6] = (IHDR_Height + 0) / 2;
-
- /*
- * information for un-filtering
- */
-
- switch(IHDR->ColourType)
- {
- case PNG_ColourType_Grey :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_1 :
- case PNG_BitDepth_2 :
- case PNG_BitDepth_4 :
- {
- BytesPerPixel = 1;
- PixelsPerByte = 8 / IHDR->BitDepth;
-
- break;
- }
-
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_Grey;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_True :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_True;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_Indexed :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_1 :
- case PNG_BitDepth_2 :
- case PNG_BitDepth_4 :
- {
- BytesPerPixel = 1;
- PixelsPerByte = 8 / IHDR->BitDepth;
-
- break;
- }
-
- case PNG_BitDepth_8 :
- {
- BytesPerPixel = PNG_NumColourComponents_Indexed;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_GreyAlpha :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_GreyAlpha;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- case PNG_ColourType_TrueAlpha :
- {
- switch(IHDR->BitDepth)
- {
- case PNG_BitDepth_8 :
- case PNG_BitDepth_16 :
- {
- BytesPerPixel = (IHDR->BitDepth / 8) * PNG_NumColourComponents_TrueAlpha;
- PixelsPerByte = 1;
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- break;
- }
-
- default :
- {
- return(qfalse);
- }
- }
-
- /*
- * Calculate the size of the scanlines per pass
- */
-
- for(a = 0; a < PNG_Adam7_NumPasses; a++)
- {
- BytesPerScanline[a] = (PassWidth[a] * BytesPerPixel + (PixelsPerByte - 1)) / PixelsPerByte;
- }
-
- /*
- * Calculate the size of all passes
- */
-
- TargetLength = 0;
-
- for(a = 0; a < PNG_Adam7_NumPasses; a++)
- {
- TargetLength += ((BytesPerScanline[a] + (BytesPerScanline[a] ? 1 : 0)) * PassHeight[a]);
- }
-
- /*
- * Check if we have enough data for the whole image.
- */
-
- if(!(DecompressedDataLength == TargetLength))
- {
- return(qfalse);
- }
-
- /*
- * Unfilter the image.
- */
-
- DecompPtr = DecompressedData;
-
- for(a = 0; a < PNG_Adam7_NumPasses; a++)
- {
- if(!UnfilterImage(DecompPtr, PassHeight[a], BytesPerScanline[a], BytesPerPixel))
- {
- return(qfalse);
- }
-
- DecompPtr += ((BytesPerScanline[a] + (BytesPerScanline[a] ? 1 : 0)) * PassHeight[a]);
- }
-
- /*
- * Set the working pointers to the beginning of the buffers.
- */
-
- DecompPtr = DecompressedData;
-
- /*
- * Create the output image.
- */
-
- for(a = 0; a < PNG_Adam7_NumPasses; a++)
- {
- for(h = 0; h < PassHeight[a]; h++)
- {
- /*
- * Count the pixels on the scanline for those multipixel bytes
- */
-
- uint32_t CurrPixel;
-
- /*
- * skip FilterType
- */
-
- DecompPtr++;
-
- /*
- * Reset the pixel count.
- */
-
- CurrPixel = 0;
-
- for(w = 0; w < (BytesPerScanline[a] / BytesPerPixel); w++)
- {
- if(PixelsPerByte > 1)
- {
- uint8_t Mask;
- uint32_t Shift;
- uint8_t SinglePixel;
-
- for(p = 0; p < PixelsPerByte; p++)
- {
- if(CurrPixel < PassWidth[a])
- {
- Mask = (1 << IHDR->BitDepth) - 1;
- Shift = (PixelsPerByte - 1 - p) * IHDR->BitDepth;
-
- SinglePixel = ((DecompPtr[0] & (Mask << Shift)) >> Shift);
-
- OutPtr = OutBuffer + (((((h * HSkip[a]) + HOffset[a]) * IHDR_Width) + ((CurrPixel * WSkip[a]) + WOffset[a])) * Q3IMAGE_BYTESPERPIXEL);
-
- if(!ConvertPixel(IHDR, OutPtr, &SinglePixel, HasTransparentColour, TransparentColour, OutPal))
- {
- return(qfalse);
- }
-
- CurrPixel++;
- }
- }
-
- }
- else
- {
- OutPtr = OutBuffer + (((((h * HSkip[a]) + HOffset[a]) * IHDR_Width) + ((w * WSkip[a]) + WOffset[a])) * Q3IMAGE_BYTESPERPIXEL);
-
- if(!ConvertPixel(IHDR, OutPtr, DecompPtr, HasTransparentColour, TransparentColour, OutPal))
- {
- return(qfalse);
- }
- }
-
- DecompPtr += BytesPerPixel;
- }
- }
- }
-
- return(qtrue);
-}
-
-/*
- * The PNG loader
- */
-
-static void LoadPNG(const char *name, byte **pic, int *width, int *height)
-{
- struct BufferedFile *ThePNG;
- byte *OutBuffer;
- uint8_t *Signature;
- struct PNG_ChunkHeader *CH;
- uint32_t ChunkHeaderLength;
- uint32_t ChunkHeaderType;
- struct PNG_Chunk_IHDR *IHDR;
- uint32_t IHDR_Width;
- uint32_t IHDR_Height;
- PNG_ChunkCRC *CRC;
- uint8_t *InPal;
- uint8_t *DecompressedData;
- uint32_t DecompressedDataLength;
- uint32_t i;
-
- /*
- * palette with 256 RGBA entries
- */
-
- uint8_t OutPal[1024];
-
- /*
- * transparent colour from the tRNS chunk
- */
-
- qboolean HasTransparentColour = qfalse;
- uint8_t TransparentColour[6] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
-
- /*
- * input verification
- */
-
- if(!(name && pic))
- {
- return;
- }
-
- /*
- * Zero out return values.
- */
-
- *pic = NULL;
-
- if(width)
- {
- *width = 0;
- }
-
- if(height)
- {
- *height = 0;
- }
-
- /*
- * Read the file.
- */
-
- ThePNG = ReadBufferedFile(name);
- if(!ThePNG)
- {
- return;
- }
-
- /*
- * Read the siganture of the file.
- */
-
- Signature = BufferedFileRead(ThePNG, PNG_Signature_Size);
- if(!Signature)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Is it a PNG?
- */
-
- if(memcmp(Signature, PNG_Signature, PNG_Signature_Size))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the first chunk-header.
- */
-
- CH = BufferedFileRead(ThePNG, PNG_ChunkHeader_Size);
- if(!CH)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * PNG multi-byte types are in Big Endian
- */
-
- ChunkHeaderLength = BigLong(CH->Length);
- ChunkHeaderType = BigLong(CH->Type);
-
- /*
- * Check if the first chunk is an IHDR.
- */
-
- if(!((ChunkHeaderType == PNG_ChunkType_IHDR) && (ChunkHeaderLength == PNG_Chunk_IHDR_Size)))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the IHDR.
- */
-
- IHDR = BufferedFileRead(ThePNG, PNG_Chunk_IHDR_Size);
- if(!IHDR)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the CRC for IHDR
- */
-
- CRC = BufferedFileRead(ThePNG, PNG_ChunkCRC_Size);
- if(!CRC)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Here we could check the CRC if we wanted to.
- */
-
- /*
- * multi-byte type swapping
- */
-
- IHDR_Width = BigLong(IHDR->Width);
- IHDR_Height = BigLong(IHDR->Height);
-
- /*
- * Check if Width and Height are valid.
- */
-
- if(!((IHDR_Width > 0) && (IHDR_Height > 0)))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Do we need to check if the dimensions of the image are valid for Quake3?
- */
-
- /*
- * Check if CompressionMethod and FilterMethod are valid.
- */
-
- if(!((IHDR->CompressionMethod == PNG_CompressionMethod_0) && (IHDR->FilterMethod == PNG_FilterMethod_0)))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Check if InterlaceMethod is valid.
- */
-
- if(!((IHDR->InterlaceMethod == PNG_InterlaceMethod_NonInterlaced) || (IHDR->InterlaceMethod == PNG_InterlaceMethod_Interlaced)))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read palette for an indexed image.
- */
-
- if(IHDR->ColourType == PNG_ColourType_Indexed)
- {
- /*
- * We need the palette first.
- */
-
- if(!FindChunk(ThePNG, PNG_ChunkType_PLTE))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the chunk-header.
- */
-
- CH = BufferedFileRead(ThePNG, PNG_ChunkHeader_Size);
- if(!CH)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * PNG multi-byte types are in Big Endian
- */
-
- ChunkHeaderLength = BigLong(CH->Length);
- ChunkHeaderType = BigLong(CH->Type);
-
- /*
- * Check if the chunk is an PLTE.
- */
-
- if(!(ChunkHeaderType == PNG_ChunkType_PLTE))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Check if Length is divisible by 3
- */
-
- if(ChunkHeaderLength % 3)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the raw palette data
- */
-
- InPal = BufferedFileRead(ThePNG, ChunkHeaderLength);
- if(!InPal)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the CRC for the palette
- */
-
- CRC = BufferedFileRead(ThePNG, PNG_ChunkCRC_Size);
- if(!CRC)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Set some default values.
- */
-
- for(i = 0; i < 256; i++)
- {
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 0] = 0x00;
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 1] = 0x00;
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 2] = 0x00;
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 3] = 0xFF;
- }
-
- /*
- * Convert to the Quake3 RGBA-format.
- */
-
- for(i = 0; i < (ChunkHeaderLength / 3); i++)
- {
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 0] = InPal[i*3+0];
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 1] = InPal[i*3+1];
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 2] = InPal[i*3+2];
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 3] = 0xFF;
- }
- }
-
- /*
- * transparency information is sometimes stored in an tRNS chunk
- */
-
- /*
- * Let's see if there is a tRNS chunk
- */
-
- if(FindChunk(ThePNG, PNG_ChunkType_tRNS))
- {
- uint8_t *Trans;
-
- /*
- * Read the chunk-header.
- */
-
- CH = BufferedFileRead(ThePNG, PNG_ChunkHeader_Size);
- if(!CH)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * PNG multi-byte types are in Big Endian
- */
-
- ChunkHeaderLength = BigLong(CH->Length);
- ChunkHeaderType = BigLong(CH->Type);
-
- /*
- * Check if the chunk is an tRNS.
- */
-
- if(!(ChunkHeaderType == PNG_ChunkType_tRNS))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the transparency information.
- */
-
- Trans = BufferedFileRead(ThePNG, ChunkHeaderLength);
- if(!Trans)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Read the CRC.
- */
-
- CRC = BufferedFileRead(ThePNG, PNG_ChunkCRC_Size);
- if(!CRC)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Only for Grey, True and Indexed ColourType should tRNS exist.
- */
-
- switch(IHDR->ColourType)
- {
- case PNG_ColourType_Grey :
- {
- if(!ChunkHeaderLength == 2)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- HasTransparentColour = qtrue;
-
- /*
- * Grey can have one colour which is completely transparent.
- * This colour is always stored in 16 bits.
- */
-
- TransparentColour[0] = Trans[0];
- TransparentColour[1] = Trans[1];
-
- break;
- }
-
- case PNG_ColourType_True :
- {
- if(!ChunkHeaderLength == 6)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- HasTransparentColour = qtrue;
-
- /*
- * True can have one colour which is completely transparent.
- * This colour is always stored in 16 bits.
- */
-
- TransparentColour[0] = Trans[0];
- TransparentColour[1] = Trans[1];
- TransparentColour[2] = Trans[2];
- TransparentColour[3] = Trans[3];
- TransparentColour[4] = Trans[4];
- TransparentColour[5] = Trans[5];
-
- break;
- }
-
- case PNG_ColourType_Indexed :
- {
- /*
- * Maximum of 256 one byte transparency entries.
- */
-
- if(ChunkHeaderLength > 256)
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- HasTransparentColour = qtrue;
-
- /*
- * alpha values for palette entries
- */
-
- for(i = 0; i < ChunkHeaderLength; i++)
- {
- OutPal[i * Q3IMAGE_BYTESPERPIXEL + 3] = Trans[i];
- }
-
- break;
- }
-
- /*
- * All other ColourTypes should not have tRNS chunks
- */
-
- default :
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
- }
- }
-
- /*
- * Rewind to the start of the file.
- */
-
- if(!BufferedFileRewind(ThePNG, -1))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Skip the signature
- */
-
- if(!BufferedFileSkip(ThePNG, PNG_Signature_Size))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Decompress all IDAT chunks
- */
-
- DecompressedDataLength = DecompressIDATs(ThePNG, &DecompressedData);
- if(!(DecompressedDataLength && DecompressedData))
- {
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Allocate output buffer.
- */
-
- OutBuffer = ri.Malloc(IHDR_Width * IHDR_Height * Q3IMAGE_BYTESPERPIXEL);
- if(!OutBuffer)
- {
- ri.Free(DecompressedData);
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- /*
- * Interlaced and Non-interlaced images need to be handled differently.
- */
-
- switch(IHDR->InterlaceMethod)
- {
- case PNG_InterlaceMethod_NonInterlaced :
- {
- if(!DecodeImageNonInterlaced(IHDR, OutBuffer, DecompressedData, DecompressedDataLength, HasTransparentColour, TransparentColour, OutPal))
- {
- ri.Free(OutBuffer);
- ri.Free(DecompressedData);
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- break;
- }
-
- case PNG_InterlaceMethod_Interlaced :
- {
- if(!DecodeImageInterlaced(IHDR, OutBuffer, DecompressedData, DecompressedDataLength, HasTransparentColour, TransparentColour, OutPal))
- {
- ri.Free(OutBuffer);
- ri.Free(DecompressedData);
- CloseBufferedFile(ThePNG);
-
- return;
- }
-
- break;
- }
-
- default :
- {
- ri.Free(OutBuffer);
- ri.Free(DecompressedData);
- CloseBufferedFile(ThePNG);
-
- return;
- }
- }
-
- /*
- * update the pointer to the image data
- */
-
- *pic = OutBuffer;
-
- /*
- * Fill width and height.
- */
-
- if(width)
- {
- *width = IHDR_Width;
- }
-
- if(height)
- {
- *height = IHDR_Height;
- }
-
- /*
- * DecompressedData is not needed anymore.
- */
-
- ri.Free(DecompressedData);
-
- /*
- * We have all data, so close the file.
- */
-
- CloseBufferedFile(ThePNG);
-}
-
-//===================================================================
-
typedef struct
{
char *ext;
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 09:40:26 +0000