2003/10/29 04:06:21

darcs-hash:20040130074035-3ac31-54458830cf157ab77e5a2669d88fbb6b97abd1bf.gz

diff --git a/src/org/xwt/plat/Win32.cc b/src/org/xwt/plat/Win32.cc
index 95fe5f7..9cdb62b 100644 (file)
--- a/src/org/xwt/plat/Win32.cc
+++ b/src/org/xwt/plat/Win32.cc
@@ -354,12 +354,21 @@ static jint* scratch_bits = NULL;
 static jint scratch_w = 0;
 static jint scratch_h = 0;
 
+#define max(a,b) ((a)>(b)?(a):(b))
+#define min(a,b) ((a)<(b)?(a):(b))
+
 void org::xwt::plat::Win32$Win32PixelBuffer::drawPicture(org::xwt::Picture* source0,
                                                          jint dx, jint dy,
                                                          jint cx1, jint cy1, jint cx2, jint cy2,
                                                          jint rgb, jboolean alphaOnly) {
     org::xwt::plat::Win32$Win32Picture* source = (org::xwt::plat::Win32$Win32Picture*)source0;
 
+    cx1 = max(dx, cx1);
+    cy1 = max(dy, cy1);
+    cx2 = min(dx + source->getWidth(), cx2);
+    cy2 = min(dy + source->getHeight(), cy2);
+    if (cx1 >= cx2 || cy1 >= cy2) return; 
+
     if (source->hasalpha) {
 
         if (scratch == NULL || scratch_w < cx2 - cx1 || scratch_h < cy2 - cy1) {
@@ -403,16 +412,16 @@ void org::xwt::plat::Win32$Win32PixelBuffer::drawPicture(org::xwt::Picture* sour
             }
 
         // copy back from scratch to screen
-        BitBlt((HDC)hdc, cx1, cy1, cx2, cy2, (HDC)scratch_dc, 0, 0, SRCCOPY);
+        BitBlt((HDC)hdc, cx1, cy1, cx2 - cx1, cy2 - cy1, (HDC)scratch_dc, 0, 0, SRCCOPY);
 
     } else {
 
         // FIXME: support alphaOnly case here
         if (source->hasmask) {
-            BitBlt((HDC)hdc, cx1, cy1, cx2, cy2, (HDC)source->maskdc, cx1 - dx, cy1 - dy, SRCAND);
-            BitBlt((HDC)hdc, cx1, cy1, cx2, cy2, (HDC)source->hdc, cx1 - dx, cy1 - dy, SRCPAINT);
+            BitBlt((HDC)hdc, cx1, cy1, cx2 - cx1, cy2 - cy1, (HDC)source->maskdc, cx1 - dx, cy1 - dy, SRCAND);
+            BitBlt((HDC)hdc, cx1, cy1, cx2 - cx1, cy2 - cy1, (HDC)source->hdc, cx1 - dx, cy1 - dy, SRCPAINT);
         } else {
-            BitBlt((HDC)hdc, cx1, cy1, cx2, cy2, (HDC)source->hdc, cx1 - dx, cy1 - dy, SRCCOPY);
+            BitBlt((HDC)hdc, cx1, cy1, cx2 - cx1, cy2 - cy1, (HDC)source->hdc, cx1 - dx, cy1 - dy, SRCCOPY);
         }
 
     }