We're about the merge the Direct3D backend into package gpu. Extract the
raw Direct3D API to its own package, just like package glimpl.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
NewDevice creates a Device given an API, which is the necessary GPU
resources for a backend.
Convert gpu.New to take an API instead of a backend.Device directly.
In turn, this frees us to later unexport the backend package along with
the backend implementations (for now just gioui.org/gpu/gl for OpenGL).
It also allows programs that embed Gio (such as gioui.org/example/glfw)
to freely choose a backend, not just OpenGL.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Completing the goal of allowing foreign Direct3D contexts for our
D3D backend, slim down the constructor to take only the device handle.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
A previous commit removed the assumption that the output framebuffer
is constant across frames. Thus it is no longer necessary to track
and update a backend's current framebuffer when the window is resized.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
d3d11Context.Present would return a nil error if the underlying error
d3d11.ErrorCode.
While here, use defer for a resource cleanup.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Modern graphics APIs have immutable objects, with mutable data. For example,
a texture's dimensions are immutable, while the texture contents is not.
Change the GPU API abstraction to match.
Clearing a Texture is convenient to do with a plain []byte. Generalize
Texture.Upload to take a plain byte slice and introduce a helper function for
uploading *image.RGBA data.
Add TextureFormatRGBA8 a format for the linear RGB colorspace.
Add OpenGL ES 3.1 functions for compute programs.
Signed-off-by: Elias Naur <mail@eliasnaur.com>