--- a/ImageReader.st	Fri Jul 05 18:20:01 1996 +0200
+++ b/ImageReader.st	Fri Jul 05 23:00:17 1996 +0200
@@ -1474,6 +1474,90 @@
 
 !ImageReader methodsFor:'image reading'!
 
+buildMaskFromColor:maskPixelValue
+    |maskArray bytesPerMaskRow|
+
+    bytesPerMaskRow := (width+7) // 8.
+
+    maskArray := ByteArray new:bytesPerMaskRow * height.
+
+%{
+    int __w = __intVal(__INST(width));
+    int __h = __intVal(__INST(height));
+    int __x, __y;
+    int __outBits, __nOut;
+    unsigned char *__inP, *__outP, *__nextOutRow;
+    int __bpr = __intVal(bytesPerMaskRow);
+    int __maskPixel = __intVal(maskPixelValue);
+#ifdef DEBUG
+    unsigned char *outEnd;
+#endif
+
+    if (! __isByteArray(__INST(data))) goto fail;
+    if (! __isByteArray(maskArray)) goto fail;
+
+    __inP = __ByteArrayInstPtr(__INST(data))->ba_element;
+    __outP = __ByteArrayInstPtr(maskArray)->ba_element;
+
+#ifdef DEBUG
+    outEnd = __outP + (__byteArraySize(maskArray));
+#endif
+/*
+printf("outP: %x outEnd: %x sz: %d\n", __outP, outEnd, __byteArraySize(maskArray));
+*/
+
+    for (__y=__h; __y>0; __y--) {
+        __outBits = 0;
+        __nOut = 8;
+        __nextOutRow = __outP + __bpr;
+
+        for (__x=__w; __x>0; __x--) {
+            __outBits <<= 1;
+            if (*__inP != __maskPixel) {
+                __outBits |= 1;
+            }
+            __inP++;
+
+/*
+ printf("x: %d  bits: %x\n", __x, __outBits);
+*/
+            if (--__nOut == 0) {
+#ifdef DEBUG
+                if (__outP >= outEnd) {
+                 printf("oops\n");
+                 goto fail;
+                }
+#endif
+                *__outP = __outBits;
+
+                __outP++;
+                __nOut = 8;
+                __outBits = 0;
+            }
+        }
+
+        if (__nOut != 8) {
+            __outBits <<= __nOut;
+
+#ifdef DEBUG
+            if (__outP >= outEnd) {
+             printf("oops2\n");
+             goto fail;
+            }
+#endif
+            *__outP = __outBits;
+
+        }
+        __outP = __nextOutRow;
+    }
+fail: ;
+%}.
+    mask := Depth1Image width:width height:height fromArray:maskArray.
+
+    "Created: 21.6.1996 / 11:43:47 / cg"
+
+!
+
 fromStream:aStream
     "read an image in my format from aStream.
      Leave image description in instance variables."
@@ -1495,5 +1579,5 @@
 !ImageReader  class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libview/ImageReader.st,v 1.31 1996-06-21 09:54:17 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libview/ImageReader.st,v 1.32 1996-07-05 21:00:17 stefan Exp $'
 ! !