I'm running into trouble trying to figure out the best way to draw textures to the screen using Directx 11.1 (for Metro apps).
In XNA, I used SpriteBatch. Is there something partially comperable?
In the Win8 SDK examples, they used WIC and Bitmap, although it suggests that that is not the best way to draw 2D graphics with the best performance.
In XNA, I used SpriteBatch. Is there something partially comperable?
No. Direct3D is a low-level rendering system. It's job is not to make your life easier (like XNA); it's job is to provide a bare-bones interface to graphics hardware.
You do not "draw textures" in D3D. You draw triangles, which have textures mapped onto them with shaders. Two triangles form a rectangle or "quad" (short for quadrilateral), which is how you draw textures.
To do this in D3D, you need to fill a vertex buffer with the vertex positions and texture coordinates for the triangles you want to render. You will also need a (very simple) pair of shaders, vertex and pixel, which pass your positions and texture coordinates. Your pixel shader needs to use the texture coordinate it gets from the vertex shader to fetch from the texture. And that texture's color becomes the pixel shader output.
You use all of these, the two shaders, the texture, and the vertex buffer, to render.
Low-level isn't easy, and it's not meant to be.
In XNA, I used SpriteBatch. Is there something partially comperable?
Now there is, yes. :) It's called the DirectX Tool Kit. Not as full-featured and mature as XNA, but it seems to get the job done and has been created by members of the orignal XNA team. Worth checking out.
Just make a bitmap and draw it:
D2D1_SIZE_U size;
D2D1_BITMAP_PROPERTIES1 bitmapProperties;
size.width = m_width;
size.height = m_height;
bitmapProperties.bitmapOptions = D2D1_BITMAP_OPTIONS::D2D1_BITMAP_OPTIONS_NONE;
bitmapProperties.colorContext = nullptr;
bitmapProperties.dpiX = 96;
bitmapProperties.dpiY = 96;
bitmapProperties.pixelFormat.format = DXGI_FORMAT_R8G8B8A8_UNORM;
bitmapProperties.pixelFormat.alphaMode = D2D1_ALPHA_MODE::D2D1_ALPHA_MODE_PREMULTIPLIED;
ThrowIfFailed(
m_videoDevice->GetD2DDeviceContext()->CreateBitmap(size, m_data, m_pitch, &bitmapProperties, &m_bitmap)
);
m_videoDevice->GetD2DDeviceContext()->BeginDraw();
D2D1_RECT_F r;
r.left = 10;
r.bottom = 400;
r.right = 200;
r.top = 10;
m_videoDevice->GetD2DDeviceContext()->DrawBitmap(m_imageManager->GetImage("./Assets/starryAlpha.tga")->m_bitmap.Get(), &r);
// Ignore D2DERR_RECREATE_TARGET here. This error indicates that the device
// is lost. It will be handled during the next call to Present.
m_videoDevice->GetD2DDeviceContext()->EndDraw();
