1 files changed, 54 insertions, 0 deletions
diff --git a/backends/PalmOS/Src/arm/fastshrink.cpp b/backends/PalmOS/Src/arm/fastshrink.cpp
new file mode 100755
index 0000000000..b46843e793
--- /dev/null
+++ b/backends/PalmOS/Src/arm/fastshrink.cpp
@@ -0,0 +1,54 @@
+#include "native.h"
+#include "endianutils.h"
+
+#define MAIN_TYPE	FastShrinkType
+#include "macros.h"
+
+UInt32 Screen_fastShrink(void *userData68KP) {
+// import variables
+	SETPTR	(UInt8 *	,src		);
+	SET32	(UInt32,	width		);
+	SET32	(UInt32,	height		);
+	SET32	(uint32,	scale		);
+	SETPTR	(UInt8 *	,dest		);
+// end of import
+
+	uint32 resHeight = (height * scale) >> 8;
+	uint32 resWidth = (width * scale) >> 8;
+	uint32 step = 0x10000 / scale;
+	uint8 columnTab[160];
+	uint32 res = step >> 1;
+	for (uint16 cnt = 0; cnt < resWidth; cnt++) {
+		columnTab[cnt] = (uint8)(res >> 8);
+		res += step;
+	}
+
+	uint32 newRow = step >> 1;
+	uint32 oldRow = 0;
+
+	uint8 *destPos = dest;
+	uint16 lnCnt;
+	for (lnCnt = 0; lnCnt < resHeight; lnCnt++) {
+		while (oldRow < (newRow >> 8)) {
+			oldRow++;
+			src += width;
+		}
+		for (uint16 colCnt = 0; colCnt < resWidth; colCnt++) {
+			*destPos++ = src[columnTab[colCnt]];
+		}
+		newRow += step;
+	}
+	// scaled, now stipple shadows if there are any
+	for (lnCnt = 0; lnCnt < resHeight; lnCnt++) {
+		uint16 xCnt = lnCnt & 1;
+		destPos = dest + lnCnt * resWidth + (lnCnt & 1);
+		while (xCnt < resWidth) {
+			if (*destPos == 200)
+				*destPos = 0;
+			destPos += 2;
+			xCnt += 2;
+		}
+	}
+	
+	return 0;
+}