backendtest: test blending of bitmap

This forces a blending of an alpha virtualdevice with a BitmapEx
which has an alpha component. This tries a fast-path with using
blendAlphaBitmap in the backend and does blending manually and
slower if the fast-path is not available.

Change-Id: I7e45dc78ce3e61ede408aa8388802a193cbc577a

1 files changed, 47 insertions, 0 deletions

diff --git a/vcl/backendtest/outputdevice/bitmap.cxx b/vcl/backendtest/outputdevice/bitmap.cxx
index dbbb052c122e..58b7c5f03ff0 100644
--- a/vcl/backendtest/outputdevice/bitmap.cxx
+++ b/vcl/backendtest/outputdevice/bitmap.cxx
@@ -112,6 +112,39 @@ Bitmap OutputDeviceTestBitmap::setupDrawMask()
     return mpVirtualDevice->GetBitmap(maVDRectangle.TopLeft(), maVDRectangle.GetSize());
 }
 
+BitmapEx OutputDeviceTestBitmap::setupDrawBlend()
+{
+    Size aBitmapSize(9, 9);
+    Bitmap aBitmap(aBitmapSize, 24);
+    {
+        BitmapScopedWriteAccess aWriteAccess(aBitmap);
+        aWriteAccess->Erase(COL_WHITE);
+        aWriteAccess->SetLineColor(Color(0xFF, 0xFF, 0x00));
+        aWriteAccess->DrawRect(tools::Rectangle(0, 0,  8, 8));
+        aWriteAccess->DrawRect(tools::Rectangle(3, 3,  5, 5));
+    }
+
+    AlphaMask aAlpha(aBitmapSize);
+    {
+        AlphaScopedWriteAccess aWriteAccess(aAlpha);
+        aWriteAccess->Erase(COL_WHITE);
+        aWriteAccess->SetLineColor(Color(0x44, 0x44, 0x44));
+        aWriteAccess->DrawRect(tools::Rectangle(0, 0, 8, 8));
+        aWriteAccess->DrawRect(tools::Rectangle(3, 3, 5, 5));
+    }
+
+    initialSetup(13, 13, constBackgroundColor, false, true);
+    mpVirtualDevice->SetFillColor(constBackgroundColor);
+    mpVirtualDevice->SetLineColor(constBackgroundColor);
+    mpVirtualDevice->DrawRect(maVDRectangle);
+
+    Point aPoint(alignToCenter(maVDRectangle, tools::Rectangle(Point(), aBitmapSize)).TopLeft());
+
+    mpVirtualDevice->DrawBitmapEx(aPoint, BitmapEx(aBitmap, aAlpha));
+
+    return mpVirtualDevice->GetBitmapEx(maVDRectangle.TopLeft(), maVDRectangle.GetSize());
+}
+
 TestResult OutputDeviceTestBitmap::checkTransformedBitmap(Bitmap& rBitmap)
 {
     std::vector<Color> aExpected
@@ -140,6 +173,20 @@ TestResult OutputDeviceTestBitmap::checkMask(Bitmap& rBitmap)
     return checkRectangle(rBitmap);
 }
 
+TestResult OutputDeviceTestBitmap::checkBlend(BitmapEx& rBitmapEx)
+{
+    const Color aBlendedColor(0xEE, 0xEE, 0x33);
+
+    std::vector<Color> aExpected
+    {
+        constBackgroundColor, constBackgroundColor,
+        aBlendedColor, constBackgroundColor, constBackgroundColor,
+        aBlendedColor, constBackgroundColor
+    };
+    Bitmap aBitmap(rBitmapEx.GetBitmap());
+    return checkRectangles(aBitmap, aExpected);
+}
+
 }} // end namespace vcl::test
 
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