Import Tk 8.6.6 (as of svn r86089)

generic/tkImgUtil.c

@@ -0,0 +1,83 @@
+/*
+ * tkImgUtil.c --
+ *
+ *	This file contains image related utility functions.
+ *
+ * Copyright (c) 1995 Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#include "tkInt.h"
+#include "xbytes.h"
+
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TkAlignImageData --
+ *
+ *	This function takes an image and copies the data into an aligned
+ *	buffer, performing any necessary bit swapping.
+ *
+ * Results:
+ *	Returns a newly allocated buffer that should be freed by the caller.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TkAlignImageData(
+    XImage *image,		/* Image to be aligned. */
+    int alignment,		/* Number of bytes to which the data should be
+				 * aligned (e.g. 2 or 4) */
+    int bitOrder)		/* Desired bit order: LSBFirst or MSBFirst. */
+{
+    long dataWidth;
+    char *data, *srcPtr, *destPtr;
+    int i, j;
+
+    if (image->bits_per_pixel != 1) {
+	Tcl_Panic(
+		"TkAlignImageData: Can't handle image depths greater than 1.");
+    }
+
+    /*
+     * Compute line width for output data buffer.
+     */
+
+    dataWidth = image->bytes_per_line;
+    if (dataWidth % alignment) {
+	dataWidth += (alignment - (dataWidth % alignment));
+    }
+
+    data = ckalloc(dataWidth * image->height);
+
+    destPtr = data;
+    for (i = 0; i < image->height; i++) {
+	srcPtr = &image->data[i * image->bytes_per_line];
+	for (j = 0; j < dataWidth; j++) {
+	    if (j >= image->bytes_per_line) {
+		*destPtr = 0;
+	    } else if (image->bitmap_bit_order != bitOrder) {
+		*destPtr = xBitReverseTable[(unsigned char)(*(srcPtr++))];
+	    } else {
+		*destPtr = *(srcPtr++);
+	    }
+	    destPtr++;
+	}
+    }
+    return data;
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */