[cairo-commit] [cairo-www] src/dotnet-gdi-rendering.mdwn

[Carl Worth]

 src/dotnet-gdi-rendering.mdwn |   58 +++++++++++++++++++++---------------------
 1 file changed, 29 insertions(+), 29 deletions(-)

New commits:
commit 357e31cb1a9674c86bc6d8af078e2c621d481d9f
Author: MikeLischke <MikeLischke at web>
Date:   Fri May 28 06:01:55 2010 -0700

    Make code appear as code.

diff --git a/src/dotnet-gdi-rendering.mdwn b/src/dotnet-gdi-rendering.mdwn
index 43b278e..5dd4ba7 100644
--- a/src/dotnet-gdi-rendering.mdwn
+++ b/src/dotnet-gdi-rendering.mdwn
@@ -1,33 +1,33 @@
 Using GDI+ Bitmap as surface can be as simple as that (given in managed C++):
 
-  // Create the target bitmap to draw to.
-  Drawing::Bitmap contentBitmap= new Drawing::Bitmap(Width, Height);
+	// Create the target bitmap to draw to.
+	Drawing::Bitmap contentBitmap= new Drawing::Bitmap(Width, Height);
 
-  // Create a Graphics object to have a device context we can pass to cairo.
-  Graphics^ g = Graphics::FromImage(contentBitmap);
-  g->SmoothingMode = SmoothingMode::HighQuality;
+	// Create a Graphics object to have a device context we can pass to cairo.
+	Graphics^ g = Graphics::FromImage(contentBitmap);
+	g->SmoothingMode = SmoothingMode::HighQuality;
 
-  // Do some drawing in GDI+ to have some initial content, like:
-  // Fill interior.
-  Brush^ brush = gcnew SolidBrush(Color::FromArgb(191, 1, 0, 0));
-  g->FillPath(brush, innerPath);
-  delete brush;
+	// Do some drawing in GDI+ to have some initial content, like:
+	// Fill interior.
+	Brush^ brush = gcnew SolidBrush(Color::FromArgb(191, 1, 0, 0));
+	g->FillPath(brush, innerPath);
+	delete brush;
 
-  // Get the device context handle from this graphics object and create a Win32 cairo surface from it.
-  IntPtr hdc= g->GetHdc();
-  cairo_surface_t* surface= cairo_win32_surface_create((HDC) hdc.ToPointer());
+	// Get the device context handle from this graphics object and create a Win32 cairo surface from it.
+	IntPtr hdc= g->GetHdc();
+	cairo_surface_t* surface= cairo_win32_surface_create((HDC) hdc.ToPointer());
 
-  // For drawing we need a cairo context.
-  cairo_t* cr= cairo_create(surface);
+	// For drawing we need a cairo context.
+	cairo_t* cr= cairo_create(surface);
 
-  // Now you are ready to draw to that using any of the cairo calls.
-  ...
+	// Now you are ready to draw to that using any of the cairo calls.
+	...
 
-  // Don't forget the cleanup.
-  cairo_destroy(cr);
-  cairo_surface_destroy(surface);
+	// Don't forget the cleanup.
+	cairo_destroy(cr);
+	cairo_surface_destroy(surface);
 
-  g->ReleaseHdc(hdc);
+	g->ReleaseHdc(hdc);
 
 This works quite well but has one big disadvantage: cairo_win32_surface_create always returns a 24bit surface. So what if we have a bitmap with an alpha channel (like a png image we loaded and want to add something to it)? With the code above the alpha channel used in your cairo commands is lost.
 
@@ -35,12 +35,12 @@ One could create a 32bit DIB surface (using cairo_win32_surface_create_with_dib)
 
 The solution to this dilemma is an image surface (e.g. you get an image surface when you load png images in cairo).
 
-  // Instead of getting an HDC and and use cairo_win32_surface we get directly
-  // to the pixels in the bitmap and create the image surface from that.
-  Imaging::BitmapData^ bitmapData= contentBitmap->LockBits(Drawing::Rectangle(0, 0, Width, Height),
-    Imaging::ImageLockMode::ReadWrite, contentBitmap->PixelFormat);
-  unsigned char* data= (unsigned char*) bitmapData->Scan0.ToPointer();
-  cairo_surface_t* surface= cairo_image_surface_create_for_data(data, CAIRO_FORMAT_ARGB32, Width, Height, bitmapData->Stride);
+	// Instead of getting an HDC and and use cairo_win32_surface we get directly
+	// to the pixels in the bitmap and create the image surface from that.
+	Imaging::BitmapData^ bitmapData= contentBitmap->LockBits(Drawing::Rectangle(0, 0, Width, Height),
+	  Imaging::ImageLockMode::ReadWrite, contentBitmap->PixelFormat);
+	unsigned char* data= (unsigned char*) bitmapData->Scan0.ToPointer();
+	cairo_surface_t* surface= cairo_image_surface_create_for_data(data, CAIRO_FORMAT_ARGB32, Width, Height, bitmapData->Stride);
 
-  // The rest is the same as above, except we have to unlock the bits after we finished drawing.
-  contentBitmap->UnlockBits(bitmapData);
+	// The rest is the same as above, except we have to unlock the bits after we finished drawing.
+	contentBitmap->UnlockBits(bitmapData);