1 files changed, 86 insertions, 0 deletions
diff --git a/redo/imagelist_windows.c b/redo/imagelist_windows.c
new file mode 100644
index 0000000..434190c
--- /dev/null
+++ b/redo/imagelist_windows.c
@@ -0,0 +1,86 @@
+// 16 august 2014
+
+#include "winapi_windows.h"
+#include "_cgo_export.h"
+
+HBITMAP unscaledBitmap(void *i, intptr_t dx, intptr_t dy)
+{
+	BITMAPINFO bi;
+	VOID *ppvBits;
+	HBITMAP bitmap;
+
+	ZeroMemory(&bi, sizeof (BITMAPINFO));
+	bi.bmiHeader.biSize = sizeof (BITMAPINFOHEADER);
+	bi.bmiHeader.biWidth = (LONG) dx;
+	bi.bmiHeader.biHeight = -((LONG) dy);			// negative height to force top-down drawing;
+	bi.bmiHeader.biPlanes = 1;
+	bi.bmiHeader.biBitCount = 32;
+	bi.bmiHeader.biCompression = BI_RGB;
+	bi.bmiHeader.biSizeImage = (DWORD) (dx * dy * 4);
+	bitmap = CreateDIBSection(NULL, &bi, DIB_RGB_COLORS, &ppvBits, 0, 0);
+	if (bitmap == NULL)
+		xpanic("error creating HBITMAP for unscaled ImageList image copy", GetLastError());
+	dotoARGB(i, (void *) ppvBits);
+	return bitmap;
+}
+
+HIMAGELIST newImageList(int width, int height)
+{
+	HIMAGELIST il;
+
+	// TODO does this strip alpha?
+	// sinni800 in irc.freenode.net/#go-nuts suggests our use of *image.RGBA makes this not so much of an issue
+	il = (*fv_ImageList_Create)(width, height, ILC_COLOR32, 20, 20);		// should be reasonable
+	if (il == NULL)
+		xpanic("error creating image list", GetLastError());
+	return il;
+}
+
+void addImage(HIMAGELIST il, HBITMAP bitmap, int origwid, int oright, int width, int height)
+{
+	BOOL wasScaled = FALSE;
+	HDC scaledDC, origDC;
+	HBITMAP scaled;
+	HBITMAP prevscaled, prevorig;
+
+	// first we need to scale the bitmap
+	if (origwid == width && oright == height) {
+		scaled = bitmap;
+		goto noscale;
+	}
+	wasScaled = TRUE;
+	scaledDC = GetDC(NULL);
+	if (scaledDC == NULL)
+		xpanic("error getting screen DC for scaled ImageList bitmap", GetLastError());
+	scaled = CreateCompatibleBitmap(scaledDC, width, height);
+	if (scaled == NULL)
+		xpanic("error creating scaled ImageList bitmap", GetLastError());
+	prevscaled = SelectObject(scaledDC, scaled);
+	if (prevscaled == NULL)
+		xpanic("error selecting scaled ImageList bitmap into screen DC", GetLastError());
+	origDC = GetDC(NULL);
+	if (origDC == NULL)
+		xpanic("error getting screen DC for original ImageList bitmap", GetLastError());
+	prevorig = SelectObject(origDC, bitmap);
+	if (prevorig == NULL)
+		xpanic("error selecting original ImageList bitmap into screen DC", GetLastError());
+	if (StretchBlt(scaledDC, 0, 0, width, height,
+		origDC, 0, 0, origwid, oright,
+		SRCCOPY) == 0)
+		xpanic("error scaling ImageList bitmap down", GetLastError());
+	if (SelectObject(origDC, prevorig) != bitmap)
+		xpanic("error selecting previous bitmap into original image's screen DC", GetLastError());
+	if (DeleteDC(origDC) == 0)
+		xpanic("error deleting original image's screen DC", GetLastError());
+	if (SelectObject(scaledDC, prevscaled) != scaled)
+		xpanic("error selecting previous bitmap into scaled image's screen DC", GetLastError());
+	if (DeleteDC(scaledDC) == 0)
+		xpanic("error deleting scaled image's screen DC", GetLastError());
+
+noscale:
+	if ((*fv_ImageList_Add)(il, scaled, NULL) == -1)
+		xpanic("error adding ImageList image to image list", GetLastError());
+	if (wasScaled)		// clean up
+		if (DeleteObject(scaled) == 0)
+			xpanic("error deleting scaled bitmap", GetLastError());
+}