A recent change made the OpenGL functions an interface of the functions
required for the implementation of GPU, a renderer for Gio operations.
That allowed for running Gio on external systems where OpenGL is
available.
However, to allow for non-OpenGL flavored backends such as Vulkan,
Metal and Direct3D, this change introduces Backend for the high-level
operations required by GPU. This change also adds a concrete backend
to package gl.
Type Backend is a first cut heavily based on OpenGL. Future changes will add
more backends, where the Backend interface quite possibly will need refinement.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The ability to invoke other operation lists belongs in the new CallOp.
While we're here, make MacroOp.Add use a pointer receiver to match the
other methods.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We'd like to improve the API of Flex, Stack and similar layouts
that use MacroOps internall. Unfortunately, the
func (m MacroOp) Add(o *Ops)
method causes the MacroOp to be allocated on the heap, ruining the
nice garbage-free property of layouts.
Fortunately, layouts don't need the feature that caused the heap
allocation: invoking operation lists different than the current.
CallOp separates the invoke-different-list semantic from MacroOp,
in preparation for removing the feature from MacroOp.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The code tried to extract a rounded whole number of pixels while preserving the
fraction. However, it failed to converge for the value 0.5, rounded to 1,
leaving -0.5, rounded to -1, leaving 0.5 and so on.
Drop the cleverness and truncate the values instead.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The gioui.org/commit/74407a50d598bfd27e8f8e48b6832cc5df04de77
added a NewImageOp constructor that always copies the supplied
image. It does that for two reasons:
First, the image.Image reference is used in the image=>texture
map of cached textures. Without a copy, we wouldn't detect a
modified image even if a new ImageOp was created.
Second, we don't want the program to touch the image while the GPU
is uploading it.
The second reason was removed in a previous change that blocks
FrameEvent.Frame until we're done with the operations, including
uploading images to the GPU.
The first reason is easily fixed by using a unique per ImageOp,
as pointed out by Alessandro Arzilli.
This change switches to using the unique key. Alessandro's patch
avoids the copy when possible.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Package ui is now only about units except for the Config.Now method.
Remove Now and rename Config to Converter. Add layout.Config to
replace the old ui.Config.
Signed-off-by: Elias Naur <mail@eliasnaur.com>