Import Tk 8.5.15 (as of svn r89086)
This commit is contained in:
Zachary Ware
822
generic/tkImgPPM.c
Normal file
822
generic/tkImgPPM.c
Normal file
@@ -0,0 +1,822 @@
|
||||
/*
|
||||
* tkImgPPM.c --
|
||||
*
|
||||
* A photo image file handler for PPM (Portable PixMap) files.
|
||||
*
|
||||
* Copyright (c) 1994 The Australian National University.
|
||||
* Copyright (c) 1994-1997 Sun Microsystems, Inc.
|
||||
*
|
||||
* See the file "license.terms" for information on usage and redistribution of
|
||||
* this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
*
|
||||
* Author: Paul Mackerras (paulus@cs.anu.edu.au),
|
||||
* Department of Computer Science,
|
||||
* Australian National University.
|
||||
*/
|
||||
|
||||
#include "tkInt.h"
|
||||
|
||||
/*
|
||||
* The maximum amount of memory to allocate for data read from the file. If we
|
||||
* need more than this, we do it in pieces.
|
||||
*/
|
||||
|
||||
#define MAX_MEMORY 10000 /* don't allocate > 10KB */
|
||||
|
||||
/*
|
||||
* Define PGM and PPM, i.e. gray images and color images.
|
||||
*/
|
||||
|
||||
#define PGM 1
|
||||
#define PPM 2
|
||||
|
||||
/*
|
||||
* The format record for the PPM file format:
|
||||
*/
|
||||
|
||||
static int FileMatchPPM(Tcl_Channel chan, CONST char *fileName,
|
||||
Tcl_Obj *format, int *widthPtr, int *heightPtr,
|
||||
Tcl_Interp *interp);
|
||||
static int FileReadPPM(Tcl_Interp *interp, Tcl_Channel chan,
|
||||
CONST char *fileName, Tcl_Obj *format,
|
||||
Tk_PhotoHandle imageHandle, int destX, int destY,
|
||||
int width, int height, int srcX, int srcY);
|
||||
static int FileWritePPM(Tcl_Interp *interp, CONST char *fileName,
|
||||
Tcl_Obj *format, Tk_PhotoImageBlock *blockPtr);
|
||||
static int StringWritePPM(Tcl_Interp *interp, Tcl_Obj *format,
|
||||
Tk_PhotoImageBlock *blockPtr);
|
||||
static int StringMatchPPM(Tcl_Obj *dataObj, Tcl_Obj *format,
|
||||
int *widthPtr, int *heightPtr, Tcl_Interp *interp);
|
||||
static int StringReadPPM(Tcl_Interp *interp, Tcl_Obj *dataObj,
|
||||
Tcl_Obj *format, Tk_PhotoHandle imageHandle,
|
||||
int destX, int destY, int width, int height,
|
||||
int srcX, int srcY);
|
||||
|
||||
Tk_PhotoImageFormat tkImgFmtPPM = {
|
||||
"ppm", /* name */
|
||||
FileMatchPPM, /* fileMatchProc */
|
||||
StringMatchPPM, /* stringMatchProc */
|
||||
FileReadPPM, /* fileReadProc */
|
||||
StringReadPPM, /* stringReadProc */
|
||||
FileWritePPM, /* fileWriteProc */
|
||||
StringWritePPM, /* stringWriteProc */
|
||||
};
|
||||
|
||||
/*
|
||||
* Prototypes for local functions defined in this file:
|
||||
*/
|
||||
|
||||
static int ReadPPMFileHeader(Tcl_Channel chan, int *widthPtr,
|
||||
int *heightPtr, int *maxIntensityPtr);
|
||||
static int ReadPPMStringHeader(Tcl_Obj *dataObj, int *widthPtr,
|
||||
int *heightPtr, int *maxIntensityPtr,
|
||||
unsigned char **dataBufferPtr, int *dataSizePtr);
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* FileMatchPPM --
|
||||
*
|
||||
* This function is invoked by the photo image type to see if a file
|
||||
* contains image data in PPM format.
|
||||
*
|
||||
* Results:
|
||||
* The return value is >0 if the first characters in file "f" look like
|
||||
* PPM data, and 0 otherwise.
|
||||
*
|
||||
* Side effects:
|
||||
* The access position in f may change.
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
FileMatchPPM(
|
||||
Tcl_Channel chan, /* The image file, open for reading. */
|
||||
CONST char *fileName, /* The name of the image file. */
|
||||
Tcl_Obj *format, /* User-specified format string, or NULL. */
|
||||
int *widthPtr, int *heightPtr,
|
||||
/* The dimensions of the image are returned
|
||||
* here if the file is a valid raw PPM
|
||||
* file. */
|
||||
Tcl_Interp *interp) /* unused */
|
||||
{
|
||||
int dummy;
|
||||
|
||||
return ReadPPMFileHeader(chan, widthPtr, heightPtr, &dummy);
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* FileReadPPM --
|
||||
*
|
||||
* This function is called by the photo image type to read PPM format
|
||||
* data from a file and write it into a given photo image.
|
||||
*
|
||||
* Results:
|
||||
* A standard TCL completion code. If TCL_ERROR is returned then an error
|
||||
* message is left in the interp's result.
|
||||
*
|
||||
* Side effects:
|
||||
* The access position in file f is changed, and new data is added to the
|
||||
* image given by imageHandle.
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
FileReadPPM(
|
||||
Tcl_Interp *interp, /* Interpreter to use for reporting errors. */
|
||||
Tcl_Channel chan, /* The image file, open for reading. */
|
||||
CONST char *fileName, /* The name of the image file. */
|
||||
Tcl_Obj *format, /* User-specified format string, or NULL. */
|
||||
Tk_PhotoHandle imageHandle, /* The photo image to write into. */
|
||||
int destX, int destY, /* Coordinates of top-left pixel in photo
|
||||
* image to be written to. */
|
||||
int width, int height, /* Dimensions of block of photo image to be
|
||||
* written to. */
|
||||
int srcX, int srcY) /* Coordinates of top-left pixel to be used in
|
||||
* image being read. */
|
||||
{
|
||||
int fileWidth, fileHeight, maxIntensity;
|
||||
int nLines, nBytes, h, type, count;
|
||||
unsigned char *pixelPtr;
|
||||
Tk_PhotoImageBlock block;
|
||||
|
||||
type = ReadPPMFileHeader(chan, &fileWidth, &fileHeight, &maxIntensity);
|
||||
if (type == 0) {
|
||||
Tcl_AppendResult(interp, "couldn't read raw PPM header from file \"",
|
||||
fileName, "\"", NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
if ((fileWidth <= 0) || (fileHeight <= 0)) {
|
||||
Tcl_AppendResult(interp, "PPM image file \"", fileName,
|
||||
"\" has dimension(s) <= 0", NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
if ((maxIntensity <= 0) || (maxIntensity >= 256)) {
|
||||
char buffer[TCL_INTEGER_SPACE];
|
||||
|
||||
sprintf(buffer, "%d", maxIntensity);
|
||||
Tcl_AppendResult(interp, "PPM image file \"", fileName,
|
||||
"\" has bad maximum intensity value ", buffer, NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
if ((srcX + width) > fileWidth) {
|
||||
width = fileWidth - srcX;
|
||||
}
|
||||
if ((srcY + height) > fileHeight) {
|
||||
height = fileHeight - srcY;
|
||||
}
|
||||
if ((width <= 0) || (height <= 0)
|
||||
|| (srcX >= fileWidth) || (srcY >= fileHeight)) {
|
||||
return TCL_OK;
|
||||
}
|
||||
|
||||
if (type == PGM) {
|
||||
block.pixelSize = 1;
|
||||
block.offset[0] = 0;
|
||||
block.offset[1] = 0;
|
||||
block.offset[2] = 0;
|
||||
} else {
|
||||
block.pixelSize = 3;
|
||||
block.offset[0] = 0;
|
||||
block.offset[1] = 1;
|
||||
block.offset[2] = 2;
|
||||
}
|
||||
block.offset[3] = 0;
|
||||
block.width = width;
|
||||
block.pitch = block.pixelSize * fileWidth;
|
||||
|
||||
if (Tk_PhotoExpand(interp, imageHandle,
|
||||
destX + width, destY + height) != TCL_OK) {
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
if (srcY > 0) {
|
||||
Tcl_Seek(chan, (Tcl_WideInt)(srcY * block.pitch), SEEK_CUR);
|
||||
}
|
||||
|
||||
nLines = (MAX_MEMORY + block.pitch - 1) / block.pitch;
|
||||
if (nLines > height) {
|
||||
nLines = height;
|
||||
}
|
||||
if (nLines <= 0) {
|
||||
nLines = 1;
|
||||
}
|
||||
nBytes = nLines * block.pitch;
|
||||
pixelPtr = (unsigned char *) ckalloc((unsigned) nBytes);
|
||||
block.pixelPtr = pixelPtr + srcX * block.pixelSize;
|
||||
|
||||
for (h = height; h > 0; h -= nLines) {
|
||||
if (nLines > h) {
|
||||
nLines = h;
|
||||
nBytes = nLines * block.pitch;
|
||||
}
|
||||
count = Tcl_Read(chan, (char *) pixelPtr, nBytes);
|
||||
if (count != nBytes) {
|
||||
Tcl_AppendResult(interp, "error reading PPM image file \"",
|
||||
fileName, "\": ",
|
||||
Tcl_Eof(chan) ? "not enough data" : Tcl_PosixError(interp),
|
||||
NULL);
|
||||
ckfree((char *) pixelPtr);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
if (maxIntensity != 255) {
|
||||
unsigned char *p;
|
||||
|
||||
for (p = pixelPtr; count > 0; count--, p++) {
|
||||
*p = (((int) *p) * 255)/maxIntensity;
|
||||
}
|
||||
}
|
||||
block.height = nLines;
|
||||
if (Tk_PhotoPutBlock(interp, imageHandle, &block, destX, destY,
|
||||
width, nLines, TK_PHOTO_COMPOSITE_SET) != TCL_OK) {
|
||||
ckfree((char *) pixelPtr);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
destY += nLines;
|
||||
}
|
||||
|
||||
ckfree((char *) pixelPtr);
|
||||
return TCL_OK;
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* FileWritePPM --
|
||||
*
|
||||
* This function is invoked to write image data to a file in PPM format
|
||||
* (although we can read PGM files, we never write them).
|
||||
*
|
||||
* Results:
|
||||
* A standard TCL completion code. If TCL_ERROR is returned then an error
|
||||
* message is left in the interp's result.
|
||||
*
|
||||
* Side effects:
|
||||
* Data is written to the file given by "fileName".
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
FileWritePPM(
|
||||
Tcl_Interp *interp,
|
||||
CONST char *fileName,
|
||||
Tcl_Obj *format,
|
||||
Tk_PhotoImageBlock *blockPtr)
|
||||
{
|
||||
Tcl_Channel chan;
|
||||
int w, h, greenOffset, blueOffset, nBytes;
|
||||
unsigned char *pixelPtr, *pixLinePtr;
|
||||
char header[16 + TCL_INTEGER_SPACE * 2];
|
||||
|
||||
chan = Tcl_OpenFileChannel(interp, fileName, "w", 0666);
|
||||
if (chan == NULL) {
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
if (Tcl_SetChannelOption(interp, chan, "-translation", "binary")
|
||||
!= TCL_OK) {
|
||||
Tcl_Close(NULL, chan);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
if (Tcl_SetChannelOption(interp, chan, "-encoding", "binary")
|
||||
!= TCL_OK) {
|
||||
Tcl_Close(NULL, chan);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
sprintf(header, "P6\n%d %d\n255\n", blockPtr->width, blockPtr->height);
|
||||
Tcl_Write(chan, header, -1);
|
||||
|
||||
pixLinePtr = blockPtr->pixelPtr + blockPtr->offset[0];
|
||||
greenOffset = blockPtr->offset[1] - blockPtr->offset[0];
|
||||
blueOffset = blockPtr->offset[2] - blockPtr->offset[0];
|
||||
|
||||
if ((greenOffset == 1) && (blueOffset == 2) && (blockPtr->pixelSize == 3)
|
||||
&& (blockPtr->pitch == (blockPtr->width * 3))) {
|
||||
nBytes = blockPtr->height * blockPtr->pitch;
|
||||
if (Tcl_Write(chan, (char *) pixLinePtr, nBytes) != nBytes) {
|
||||
goto writeerror;
|
||||
}
|
||||
} else {
|
||||
for (h = blockPtr->height; h > 0; h--) {
|
||||
pixelPtr = pixLinePtr;
|
||||
for (w = blockPtr->width; w > 0; w--) {
|
||||
if ( Tcl_Write(chan,(char *)&pixelPtr[0], 1) == -1 ||
|
||||
Tcl_Write(chan,(char *)&pixelPtr[greenOffset],1)==-1 ||
|
||||
Tcl_Write(chan,(char *)&pixelPtr[blueOffset],1) ==-1) {
|
||||
goto writeerror;
|
||||
}
|
||||
pixelPtr += blockPtr->pixelSize;
|
||||
}
|
||||
pixLinePtr += blockPtr->pitch;
|
||||
}
|
||||
}
|
||||
|
||||
if (Tcl_Close(NULL, chan) == 0) {
|
||||
return TCL_OK;
|
||||
}
|
||||
chan = NULL;
|
||||
|
||||
writeerror:
|
||||
Tcl_AppendResult(interp, "error writing \"", fileName, "\": ",
|
||||
Tcl_PosixError(interp), NULL);
|
||||
if (chan != NULL) {
|
||||
Tcl_Close(NULL, chan);
|
||||
}
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* StringWritePPM --
|
||||
*
|
||||
* This function is invoked to write image data to a string in PPM
|
||||
* format.
|
||||
*
|
||||
* Results:
|
||||
* A standard TCL completion code. If TCL_ERROR is returned then an error
|
||||
* message is left in the interp's result.
|
||||
*
|
||||
* Side effects:
|
||||
* None.
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
StringWritePPM(
|
||||
Tcl_Interp *interp,
|
||||
Tcl_Obj *format,
|
||||
Tk_PhotoImageBlock *blockPtr)
|
||||
{
|
||||
int w, h, size, greenOffset, blueOffset;
|
||||
unsigned char *pixLinePtr, *byteArray;
|
||||
char header[16 + TCL_INTEGER_SPACE * 2];
|
||||
Tcl_Obj *byteArrayObj;
|
||||
|
||||
sprintf(header, "P6\n%d %d\n255\n", blockPtr->width, blockPtr->height);
|
||||
|
||||
/*
|
||||
* Construct a byte array of the right size with the header and
|
||||
* get a pointer to the data part of it.
|
||||
*/
|
||||
|
||||
size = strlen(header);
|
||||
byteArrayObj = Tcl_NewByteArrayObj((unsigned char *)header, size);
|
||||
byteArray = Tcl_SetByteArrayLength(byteArrayObj,
|
||||
size + 3*blockPtr->width*blockPtr->height);
|
||||
byteArray += size;
|
||||
|
||||
pixLinePtr = blockPtr->pixelPtr + blockPtr->offset[0];
|
||||
greenOffset = blockPtr->offset[1] - blockPtr->offset[0];
|
||||
blueOffset = blockPtr->offset[2] - blockPtr->offset[0];
|
||||
|
||||
/*
|
||||
* Check if we can do the data move in single action.
|
||||
*/
|
||||
|
||||
if ((greenOffset == 1) && (blueOffset == 2) && (blockPtr->pixelSize == 3)
|
||||
&& (blockPtr->pitch == (blockPtr->width * 3))) {
|
||||
memcpy(byteArray, pixLinePtr,
|
||||
(unsigned)blockPtr->height * blockPtr->pitch);
|
||||
} else {
|
||||
for (h = blockPtr->height; h > 0; h--) {
|
||||
unsigned char *pixelPtr = pixLinePtr;
|
||||
|
||||
for (w = blockPtr->width; w > 0; w--) {
|
||||
*byteArray++ = pixelPtr[0];
|
||||
*byteArray++ = pixelPtr[greenOffset];
|
||||
*byteArray++ = pixelPtr[blueOffset];
|
||||
pixelPtr += blockPtr->pixelSize;
|
||||
}
|
||||
pixLinePtr += blockPtr->pitch;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Return the object in the interpreter result.
|
||||
*/
|
||||
|
||||
Tcl_SetObjResult(interp, byteArrayObj);
|
||||
return TCL_OK;
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* StringMatchPPM --
|
||||
*
|
||||
* This function is invoked by the photo image type to see if a string
|
||||
* contains image data in PPM format.
|
||||
*
|
||||
* Results:
|
||||
* The return value is >0 if the first characters in file "f" look like
|
||||
* PPM data, and 0 otherwise.
|
||||
*
|
||||
* Side effects:
|
||||
* The access position in f may change.
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
StringMatchPPM(
|
||||
Tcl_Obj *dataObj, /* The image data. */
|
||||
Tcl_Obj *format, /* User-specified format string, or NULL. */
|
||||
int *widthPtr, int *heightPtr,
|
||||
/* The dimensions of the image are returned
|
||||
* here if the file is a valid raw PPM
|
||||
* file. */
|
||||
Tcl_Interp *interp) /* unused */
|
||||
{
|
||||
int dummy;
|
||||
|
||||
return ReadPPMStringHeader(dataObj, widthPtr, heightPtr,
|
||||
&dummy, NULL, NULL);
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* StringReadPPM --
|
||||
*
|
||||
* This function is called by the photo image type to read PPM format
|
||||
* data from a string and write it into a given photo image.
|
||||
*
|
||||
* Results:
|
||||
* A standard TCL completion code. If TCL_ERROR is returned then an error
|
||||
* message is left in the interp's result.
|
||||
*
|
||||
* Side effects:
|
||||
* New data is added to the image given by imageHandle.
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
StringReadPPM(
|
||||
Tcl_Interp *interp, /* Interpreter to use for reporting errors. */
|
||||
Tcl_Obj *dataObj, /* The image data. */
|
||||
Tcl_Obj *format, /* User-specified format string, or NULL. */
|
||||
Tk_PhotoHandle imageHandle, /* The photo image to write into. */
|
||||
int destX, int destY, /* Coordinates of top-left pixel in photo
|
||||
* image to be written to. */
|
||||
int width, int height, /* Dimensions of block of photo image to be
|
||||
* written to. */
|
||||
int srcX, int srcY) /* Coordinates of top-left pixel to be used in
|
||||
* image being read. */
|
||||
{
|
||||
int fileWidth, fileHeight, maxIntensity;
|
||||
int nLines, nBytes, h, type, count, dataSize;
|
||||
unsigned char *pixelPtr, *dataBuffer;
|
||||
Tk_PhotoImageBlock block;
|
||||
|
||||
type = ReadPPMStringHeader(dataObj, &fileWidth, &fileHeight,
|
||||
&maxIntensity, &dataBuffer, &dataSize);
|
||||
if (type == 0) {
|
||||
Tcl_AppendResult(interp, "couldn't read raw PPM header from string",
|
||||
NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
if ((fileWidth <= 0) || (fileHeight <= 0)) {
|
||||
Tcl_AppendResult(interp, "PPM image data has dimension(s) <= 0",
|
||||
NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
if ((maxIntensity <= 0) || (maxIntensity >= 256)) {
|
||||
char buffer[TCL_INTEGER_SPACE];
|
||||
|
||||
sprintf(buffer, "%d", maxIntensity);
|
||||
Tcl_AppendResult(interp,
|
||||
"PPM image data has bad maximum intensity value ", buffer,
|
||||
NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
if ((srcX + width) > fileWidth) {
|
||||
width = fileWidth - srcX;
|
||||
}
|
||||
if ((srcY + height) > fileHeight) {
|
||||
height = fileHeight - srcY;
|
||||
}
|
||||
if ((width <= 0) || (height <= 0)
|
||||
|| (srcX >= fileWidth) || (srcY >= fileHeight)) {
|
||||
return TCL_OK;
|
||||
}
|
||||
|
||||
if (type == PGM) {
|
||||
block.pixelSize = 1;
|
||||
block.offset[0] = 0;
|
||||
block.offset[1] = 0;
|
||||
block.offset[2] = 0;
|
||||
} else {
|
||||
block.pixelSize = 3;
|
||||
block.offset[0] = 0;
|
||||
block.offset[1] = 1;
|
||||
block.offset[2] = 2;
|
||||
}
|
||||
block.offset[3] = 0;
|
||||
block.width = width;
|
||||
block.pitch = block.pixelSize * fileWidth;
|
||||
|
||||
if (srcY > 0) {
|
||||
dataBuffer += srcY * block.pitch;
|
||||
dataSize -= srcY * block.pitch;
|
||||
}
|
||||
|
||||
if (maxIntensity == 255) {
|
||||
/*
|
||||
* We have all the data in memory, so write everything in one go.
|
||||
*/
|
||||
|
||||
if (block.pitch*height > dataSize) {
|
||||
Tcl_AppendResult(interp, "truncated PPM data", NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
block.pixelPtr = dataBuffer + srcX * block.pixelSize;
|
||||
block.height = height;
|
||||
return Tk_PhotoPutBlock(interp, imageHandle, &block, destX, destY,
|
||||
width, height, TK_PHOTO_COMPOSITE_SET);
|
||||
}
|
||||
|
||||
if (Tk_PhotoExpand(interp, imageHandle,
|
||||
destX + width, destY + height) != TCL_OK) {
|
||||
return TCL_ERROR;
|
||||
}
|
||||
|
||||
nLines = (MAX_MEMORY + block.pitch - 1) / block.pitch;
|
||||
if (nLines > height) {
|
||||
nLines = height;
|
||||
}
|
||||
if (nLines <= 0) {
|
||||
nLines = 1;
|
||||
}
|
||||
nBytes = nLines * block.pitch;
|
||||
pixelPtr = (unsigned char *) ckalloc((unsigned) nBytes);
|
||||
block.pixelPtr = pixelPtr + srcX * block.pixelSize;
|
||||
|
||||
for (h = height; h > 0; h -= nLines) {
|
||||
unsigned char *p;
|
||||
|
||||
if (nLines > h) {
|
||||
nLines = h;
|
||||
nBytes = nLines * block.pitch;
|
||||
}
|
||||
if (dataSize < nBytes) {
|
||||
ckfree((char *) pixelPtr);
|
||||
Tcl_AppendResult(interp, "truncated PPM data", NULL);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
for (p=pixelPtr,count=nBytes ; count>0 ; count--,p++,dataBuffer++) {
|
||||
*p = (((int) *dataBuffer) * 255)/maxIntensity;
|
||||
}
|
||||
dataSize -= nBytes;
|
||||
block.height = nLines;
|
||||
if (Tk_PhotoPutBlock(interp, imageHandle, &block, destX, destY,
|
||||
width, nLines, TK_PHOTO_COMPOSITE_SET) != TCL_OK) {
|
||||
ckfree((char *) pixelPtr);
|
||||
return TCL_ERROR;
|
||||
}
|
||||
destY += nLines;
|
||||
}
|
||||
|
||||
ckfree((char *) pixelPtr);
|
||||
return TCL_OK;
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* ReadPPMFileHeader --
|
||||
*
|
||||
* This function reads the PPM header from the beginning of a PPM file
|
||||
* and returns information from the header.
|
||||
*
|
||||
* Results:
|
||||
* The return value is PGM if file "f" appears to start with a valid PGM
|
||||
* header, PPM if "f" appears to start with a valid PPM header, and 0
|
||||
* otherwise. If the header is valid, then *widthPtr and *heightPtr are
|
||||
* modified to hold the dimensions of the image and *maxIntensityPtr is
|
||||
* modified to hold the value of a "fully on" intensity value.
|
||||
*
|
||||
* Side effects:
|
||||
* The access position in f advances.
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
ReadPPMFileHeader(
|
||||
Tcl_Channel chan, /* Image file to read the header from. */
|
||||
int *widthPtr, int *heightPtr,
|
||||
/* The dimensions of the image are returned
|
||||
* here. */
|
||||
int *maxIntensityPtr) /* The maximum intensity value for the image
|
||||
* is stored here. */
|
||||
{
|
||||
#define BUFFER_SIZE 1000
|
||||
char buffer[BUFFER_SIZE], c;
|
||||
int i, numFields, type = 0;
|
||||
|
||||
/*
|
||||
* Read 4 space-separated fields from the file, ignoring comments (any
|
||||
* line that starts with "#").
|
||||
*/
|
||||
|
||||
if (Tcl_Read(chan, &c, 1) != 1) {
|
||||
return 0;
|
||||
}
|
||||
i = 0;
|
||||
for (numFields = 0; numFields < 4; numFields++) {
|
||||
/*
|
||||
* Skip comments and white space.
|
||||
*/
|
||||
|
||||
while (1) {
|
||||
while (isspace(UCHAR(c))) {
|
||||
if (Tcl_Read(chan, &c, 1) != 1) {
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
if (c != '#') {
|
||||
break;
|
||||
}
|
||||
do {
|
||||
if (Tcl_Read(chan, &c, 1) != 1) {
|
||||
return 0;
|
||||
}
|
||||
} while (c != '\n');
|
||||
}
|
||||
|
||||
/*
|
||||
* Read a field (everything up to the next white space).
|
||||
*/
|
||||
|
||||
while (!isspace(UCHAR(c))) {
|
||||
if (i < (BUFFER_SIZE-2)) {
|
||||
buffer[i] = c;
|
||||
i++;
|
||||
}
|
||||
if (Tcl_Read(chan, &c, 1) != 1) {
|
||||
goto done;
|
||||
}
|
||||
}
|
||||
if (i < (BUFFER_SIZE-1)) {
|
||||
buffer[i] = ' ';
|
||||
i++;
|
||||
}
|
||||
}
|
||||
|
||||
done:
|
||||
buffer[i] = 0;
|
||||
|
||||
/*
|
||||
* Parse the fields, which are: id, width, height, maxIntensity.
|
||||
*/
|
||||
|
||||
if (strncmp(buffer, "P6 ", 3) == 0) {
|
||||
type = PPM;
|
||||
} else if (strncmp(buffer, "P5 ", 3) == 0) {
|
||||
type = PGM;
|
||||
} else {
|
||||
return 0;
|
||||
}
|
||||
if (sscanf(buffer+3, "%d %d %d", widthPtr, heightPtr, maxIntensityPtr)
|
||||
!= 3) {
|
||||
return 0;
|
||||
}
|
||||
return type;
|
||||
}
|
||||
|
||||
/*
|
||||
*----------------------------------------------------------------------
|
||||
*
|
||||
* ReadPPMStringHeader --
|
||||
*
|
||||
* This function reads the PPM header from the beginning of a PPM-format
|
||||
* string and returns information from the header.
|
||||
*
|
||||
* Results:
|
||||
* The return value is PGM if the string appears to start with a valid
|
||||
* PGM header, PPM if the string appears to start with a valid PPM
|
||||
* header, and 0 otherwise. If the header is valid, then *widthPtr and
|
||||
* *heightPtr are modified to hold the dimensions of the image and
|
||||
* *maxIntensityPtr is modified to hold the value of a "fully on"
|
||||
* intensity value.
|
||||
*
|
||||
* Side effects:
|
||||
* None
|
||||
*
|
||||
*----------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
static int
|
||||
ReadPPMStringHeader(
|
||||
Tcl_Obj *dataPtr, /* Object to read the header from. */
|
||||
int *widthPtr, int *heightPtr,
|
||||
/* The dimensions of the image are returned
|
||||
* here. */
|
||||
int *maxIntensityPtr, /* The maximum intensity value for the image
|
||||
* is stored here. */
|
||||
unsigned char **dataBufferPtr,
|
||||
int *dataSizePtr)
|
||||
{
|
||||
#define BUFFER_SIZE 1000
|
||||
char buffer[BUFFER_SIZE], c;
|
||||
int i, numFields, dataSize, type = 0;
|
||||
unsigned char *dataBuffer;
|
||||
|
||||
dataBuffer = Tcl_GetByteArrayFromObj(dataPtr, &dataSize);
|
||||
|
||||
/*
|
||||
* Read 4 space-separated fields from the string, ignoring comments (any
|
||||
* line that starts with "#").
|
||||
*/
|
||||
|
||||
if (dataSize-- < 1) {
|
||||
return 0;
|
||||
}
|
||||
c = (char) (*dataBuffer++);
|
||||
i = 0;
|
||||
for (numFields = 0; numFields < 4; numFields++) {
|
||||
/*
|
||||
* Skip comments and white space.
|
||||
*/
|
||||
|
||||
while (1) {
|
||||
while (isspace(UCHAR(c))) {
|
||||
if (dataSize-- < 1) {
|
||||
return 0;
|
||||
}
|
||||
c = (char) (*dataBuffer++);
|
||||
}
|
||||
if (c != '#') {
|
||||
break;
|
||||
}
|
||||
do {
|
||||
if (dataSize-- < 1) {
|
||||
return 0;
|
||||
}
|
||||
c = (char) (*dataBuffer++);
|
||||
} while (c != '\n');
|
||||
}
|
||||
|
||||
/*
|
||||
* Read a field (everything up to the next white space).
|
||||
*/
|
||||
|
||||
while (!isspace(UCHAR(c))) {
|
||||
if (i < (BUFFER_SIZE-2)) {
|
||||
buffer[i] = c;
|
||||
i++;
|
||||
}
|
||||
if (dataSize-- < 1) {
|
||||
goto done;
|
||||
}
|
||||
c = (char) (*dataBuffer++);
|
||||
}
|
||||
if (i < (BUFFER_SIZE-1)) {
|
||||
buffer[i] = ' ';
|
||||
i++;
|
||||
}
|
||||
}
|
||||
|
||||
done:
|
||||
buffer[i] = 0;
|
||||
|
||||
/*
|
||||
* Parse the fields, which are: id, width, height, maxIntensity.
|
||||
*/
|
||||
|
||||
if (strncmp(buffer, "P6 ", 3) == 0) {
|
||||
type = PPM;
|
||||
} else if (strncmp(buffer, "P5 ", 3) == 0) {
|
||||
type = PGM;
|
||||
} else {
|
||||
return 0;
|
||||
}
|
||||
if (sscanf(buffer+3, "%d %d %d", widthPtr, heightPtr, maxIntensityPtr)
|
||||
!= 3) {
|
||||
return 0;
|
||||
}
|
||||
if (dataBufferPtr != NULL) {
|
||||
*dataBufferPtr = dataBuffer;
|
||||
*dataSizePtr = dataSize;
|
||||
}
|
||||
return type;
|
||||
}
|
||||
|
||||
/*
|
||||
* Local Variables:
|
||||
* mode: c
|
||||
* c-basic-offset: 4
|
||||
* fill-column: 78
|
||||
* End:
|
||||
*/
|
||||
Reference in New Issue
Block a user