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-rw-r--r--generic/tkImgGIF.c87
1 files changed, 35 insertions, 52 deletions
diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c
index 4dc466a..0b528aa 100644
--- a/generic/tkImgGIF.c
+++ b/generic/tkImgGIF.c
@@ -2,8 +2,8 @@
* tkImgGIF.c --
*
* A photo image file handler for GIF files. Reads 87a and 89a GIF
- * files. At present, there only is a file write function. GIF images may be
- * read using the -data option of the photo image. The data may be
+ * files. At present, there only is a file write function. GIF images
+ * may be read using the -data option of the photo image. The data may be
* given as a binary string in a Tcl_Obj or by representing
* the data as BASE64 encoded ascii. Derived from the giftoppm code
* found in the pbmplus package and tkImgFmtPPM.c in the tk4.0b2
@@ -29,7 +29,7 @@
* | provided "as is" without express or implied warranty. |
* +-------------------------------------------------------------------+
*
- * RCS: @(#) $Id: tkImgGIF.c,v 1.14 2000/03/30 19:44:41 ericm Exp $
+ * RCS: @(#) $Id: tkImgGIF.c,v 1.14.2.1 2000/08/05 23:53:11 hobbs Exp $
*/
/*
@@ -72,11 +72,13 @@ typedef struct mFile {
* encoding independant.
*/
-# define GIF87a "\x47\x49\x46\x38\x37\x61" /* ASCII GIF87a */
-# define GIF89a "\x47\x49\x46\x38\x39\x61" /* ASCII GIF89a */
-# define GIF_TERMINATOR 0x3b /* ASCII ; */
-# define GIF_EXTENSION 0x21 /* ASCII ! */
-# define GIF_START 0x2c /* ASCII , */
+static CONST char GIF87a[] =
+ { 0x47, 0x49, 0x46, 0x38, 0x37, 0x61, 0x00 }; /* ASCII GIF87a */
+static CONST char GIF89a[] =
+ { 0x47, 0x49, 0x46, 0x38, 0x39, 0x61, 0x00 }; /* ASCII GIF89a */
+# define GIF_TERMINATOR 0x3b /* ASCII ; */
+# define GIF_EXTENSION 0x21 /* ASCII ! */
+# define GIF_START 0x2c /* ASCII , */
/*
* HACK ALERT!! HACK ALERT!! HACK ALERT!!
@@ -1326,15 +1328,15 @@ static unsigned char mapa[MAXCOLORMAPSIZE][3];
* Definition of new functions to write GIFs
*/
-static int color _ANSI_ARGS_((int red,int green, int blue));
+static int color _ANSI_ARGS_((int red,int green, int blue,
+ unsigned char mapa[MAXCOLORMAPSIZE][3]));
static void compress _ANSI_ARGS_((int init_bits, Tcl_Channel handle,
ifunptr readValue));
static int nuevo _ANSI_ARGS_((int red, int green ,int blue,
unsigned char mapa[MAXCOLORMAPSIZE][3]));
-static int savemap _ANSI_ARGS_((Tk_PhotoImageBlock *blockPtr,
+static void savemap _ANSI_ARGS_((Tk_PhotoImageBlock *blockPtr,
unsigned char mapa[MAXCOLORMAPSIZE][3]));
static int ReadValue _ANSI_ARGS_((void));
-static int no_bits _ANSI_ARGS_((int colors));
static int
FileWriteGIF (interp, filename, format, blockPtr)
@@ -1353,9 +1355,6 @@ FileWriteGIF (interp, filename, format, blockPtr)
if (Tcl_SetChannelOption(interp, chan, "-translation", "binary") != TCL_OK) {
return TCL_ERROR;
}
- if (Tcl_SetChannelOption(interp, chan, "-encoding", "binary") != TCL_OK) {
- return TCL_ERROR;
- }
result = CommonWriteGIF(interp, chan, format, blockPtr);
if (Tcl_Close(interp, chan) == TCL_ERROR) {
@@ -1374,12 +1373,10 @@ CommonWriteGIF(interp, handle, format, blockPtr)
Tk_PhotoImageBlock *blockPtr;
{
int resolution;
- long numcolormap;
long width,height,x;
unsigned char c;
unsigned int top,left;
- int num;
top = 0;
left = 0;
@@ -1410,11 +1407,12 @@ CommonWriteGIF(interp, handle, format, blockPtr)
height=blockPtr->height;
pixelo=blockPtr->pixelPtr + blockPtr->offset[0];
pixelPitch=blockPtr->pitch;
- if ((num=savemap(blockPtr,mapa))<0) {
+ savemap(blockPtr,mapa);
+ if (num>=MAXCOLORMAPSIZE) {
Tcl_AppendResult(interp, "too many colors", (char *) NULL);
return TCL_ERROR;
}
- if (num<3) num=3;
+ if (num<2) num=2;
c=LSB(width);
Mputc(c,handle);
c=MSB(width);
@@ -1424,11 +1422,14 @@ CommonWriteGIF(interp, handle, format, blockPtr)
c=MSB(height);
Mputc(c,handle);
- c= (1 << 7) | (no_bits(num) << 4) | (no_bits(num));
+ resolution = 0;
+ while (num >> resolution) {
+ resolution++;
+ }
+ c = 111 + resolution * 17;
Mputc(c,handle);
- resolution = no_bits(num)+1;
- numcolormap=1 << resolution;
+ num = 1 << resolution;
/* background color */
@@ -1439,7 +1440,7 @@ CommonWriteGIF(interp, handle, format, blockPtr)
Mputc(c,handle);
- for (x=0; x<numcolormap ;x++) {
+ for (x=0; x<num ;x++) {
c = mapa[x][CM_RED];
Mputc(c,handle);
c = mapa[x][CM_GREEN];
@@ -1497,10 +1498,11 @@ CommonWriteGIF(interp, handle, format, blockPtr)
}
static int
-color(red, green, blue)
+color(red, green, blue, mapa)
int red;
int green;
int blue;
+ unsigned char mapa[MAXCOLORMAPSIZE][3];
{
int x;
for (x=(alphaOffset != 0);x<=MAXCOLORMAPSIZE;x++) {
@@ -1519,7 +1521,7 @@ nuevo(red, green, blue, mapa)
unsigned char mapa[MAXCOLORMAPSIZE][3];
{
int x;
- for (x=(alphaOffset != 0);x<num;x++) {
+ for (x=(alphaOffset != 0);x<=num;x++) {
if ((mapa[x][CM_RED]==red) && (mapa[x][CM_GREEN]==green) &&
(mapa[x][CM_BLUE]==blue)) {
return 0;
@@ -1528,7 +1530,7 @@ nuevo(red, green, blue, mapa)
return 1;
}
-static int
+static void
savemap(blockPtr,mapa)
Tk_PhotoImageBlock *blockPtr;
unsigned char mapa[MAXCOLORMAPSIZE][3];
@@ -1538,12 +1540,12 @@ savemap(blockPtr,mapa)
unsigned char red,green,blue;
if (alphaOffset) {
- num = 1;
+ num = 0;
mapa[0][CM_RED] = 0xd9;
mapa[0][CM_GREEN] = 0xd9;
mapa[0][CM_BLUE] = 0xd9;
} else {
- num = 0;
+ num = -1;
}
for(y=0;y<blockPtr->height;y++) {
@@ -1555,19 +1557,19 @@ savemap(blockPtr,mapa)
green = colores[greenOffset];
blue = colores[blueOffset];
if (nuevo(red,green,blue,mapa)) {
- if (num>255)
- return -1;
-
+ num++;
+ if (num>=MAXCOLORMAPSIZE) {
+ return;
+ }
mapa[num][CM_RED]=red;
mapa[num][CM_GREEN]=green;
mapa[num][CM_BLUE]=blue;
- num++;
}
}
colores += pixelSize;
}
}
- return num-1;
+ return;
}
static int
@@ -1581,7 +1583,7 @@ ReadValue()
if (alphaOffset && (pixelo[alphaOffset]==0)) {
col = 0;
} else {
- col = color(pixelo[0],pixelo[greenOffset],pixelo[blueOffset]);
+ col = color(pixelo[0],pixelo[greenOffset],pixelo[blueOffset], mapa);
}
pixelo += pixelSize;
if (--ssize <= 0) {
@@ -1593,25 +1595,6 @@ ReadValue()
return col;
}
-/*
- * Return the number of bits ( -1 ) to represent a given
- * number of colors ( ex: 256 colors => 7 ).
- */
-
-static int
-no_bits( colors )
-int colors;
-{
- register int bits = 0;
-
- colors--;
- while ( colors >> bits ) {
- bits++;
- }
-
- return (bits-1);
-}
-
/*-----------------------------------------------------------------------
generated by cgit v0.12 at 2024-11-16 19:55:02 (GMT)