From a36cede2cafb24358add82c8ab1749d7d2735451 Mon Sep 17 00:00:00 2001
From: Vincent Povirk <vincent@codeweavers.com>
Date: Sun, 5 Sep 2010 18:30:51 -0500
Subject: [PATCH 1/2] gdiplus: Add a test showing that GdipGraphicsClear replaces image data.

---
 dlls/gdiplus/tests/graphics.c |   43 +++++++++++++++++++++++++++++++++++++++++
 1 files changed, 43 insertions(+), 0 deletions(-)

diff --git a/dlls/gdiplus/tests/graphics.c b/dlls/gdiplus/tests/graphics.c
index 9fae06c..a0882f4 100644
--- a/dlls/gdiplus/tests/graphics.c
+++ b/dlls/gdiplus/tests/graphics.c
@@ -29,6 +29,18 @@
 #define expectf(expected, got) expectf_(expected, got, 0.0001)
 #define TABLE_LEN (23)
 
+static BOOL color_match(ARGB c1, ARGB c2, BYTE max_diff)
+{
+    if (abs((c1 & 0xff) - (c2 & 0xff)) > max_diff) return FALSE;
+    c1 >>= 8; c2 >>= 8;
+    if (abs((c1 & 0xff) - (c2 & 0xff)) > max_diff) return FALSE;
+    c1 >>= 8; c2 >>= 8;
+    if (abs((c1 & 0xff) - (c2 & 0xff)) > max_diff) return FALSE;
+    c1 >>= 8; c2 >>= 8;
+    if (abs((c1 & 0xff) - (c2 & 0xff)) > max_diff) return FALSE;
+    return TRUE;
+}
+
 static HWND hwnd;
 
 static void test_constructor_destructor(void)
@@ -2221,6 +2233,36 @@ static void test_fromMemoryBitmap(void)
     GdipDisposeImage((GpImage*)bitmap);
 }
 
+static void test_fromAlphaBitmap(void)
+{
+    GpStatus status;
+    GpGraphics *graphics = NULL;
+    GpBitmap *bitmap = NULL;
+    BYTE bits[64] = {0};
+    ARGB color;
+
+    status = GdipCreateBitmapFromScan0(4, 4, 16, PixelFormat32bppARGB, bits, &bitmap);
+    expect(Ok, status);
+
+    status = GdipGetImageGraphicsContext((GpImage*)bitmap, &graphics);
+    expect(Ok, status);
+
+    status = GdipGraphicsClear(graphics, 0xffffffff);
+    expect(Ok, status);
+
+    status = GdipGraphicsClear(graphics, 0x8090a0b0);
+    expect(Ok, status);
+
+    GdipDeleteGraphics(graphics);
+
+    status = GdipBitmapGetPixel(bitmap, 1, 1, &color);
+    expect(Ok, status);
+    /* GdipGraphicsClear replaces pixels rather than composing them. */
+    todo_wine ok(color_match(0x8090a0b0, color, 1), "Expected 8090a0b0, got %.8x\n", color);
+
+    GdipDisposeImage((GpImage*)bitmap);
+}
+
 static void test_GdipIsVisiblePoint(void)
 {
     GpStatus status;
@@ -3009,6 +3051,7 @@ START_TEST(graphics)
     test_clear();
     test_textcontrast();
     test_fromMemoryBitmap();
+    test_fromAlphaBitmap();
     test_string_functions();
 
     GdiplusShutdown(gdiplusToken);
-- 
1.6.3.3