BeginFrame returns the output framebuffer, and need not be as general
as the newly unexported currentFramebuffer methods.
No functional change.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Return the output framebuffer from BeginFrame, to make it clear that
it may change between frames. Delete CurrentFramebuffer which is no
longer needed.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Use dxc (DirectXShaderCompiler) for compiling, which is newer than fxc
and doesn't not fail compilation with dynamically uniform flows with
barriers.
Currently requires -directcompute to enable generating the shaders.
Signed-off-by: Egon Elbre <egonelbre@gmail.com>
We're about to change the last stage of the compute pipeline to only
accept images, not sampled textures. This change prepares materials
for pixel-aligned image copying by pre-rendering images to a texture,
applying transforms.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The iOS GL implementation doesn't optimize BufferSubData of the entire
buffer, leading to GPU stalls. The workaround is to explicitly clear the
buffer before replacing it.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Gio UI may be overlaid on top of custom graphics such as in the glfw example.
That will only work if Gio doesn't clear the screen (to white).
Signed-off-by: Elias Naur <mail@eliasnaur.com>
It turns out restoring all operation state from the moment Defer
is executed is too much; for example, a right-click pop-up needs
the transformation, but not the current clip.
Change Defer to only restore the transformation, and reset all
other state.
Other combinations may be needed in future; we'll deal with them then,
possibly by exposing the load state mask.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Push/Pop only allows saving and restoring operation state in a
stack-like manner. We're going to need restoring arbitrary state
for implementing deferred operations.
Generalize state save/restore and implement Push and Pop on top of
that.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
This CL handles rounding errors arising when splitting quads into linear
segments.
Rounding errors would lead to a pair of quad triplets (from,ctl,to) not
exactly matching.
ie: to(n-1) wouldn't exactly match from(n).
Signed-off-by: Sebastien Binet <s@sbinet.org>
The new compute renderer is much less tolerant of discontinuous paths.
In particular, it requires that clip outlines form a closed loop.
Fixes TestPaintArc when GIORENDERER=forcecompute.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The old renderer is still the default, so the new compute renderer will only be
used in the rare case the old renderer is not supported but the new is. That
happens on the Samsung J2 Prime and Moto C Android phones. Or set the
GIORENDERER environment variable to "forcecompute" to disable the old renderer:
$ GIORENDERER=forcecompute go run ...
Missing features:
- Gradients are not supported yet, and render as a solid color.
- Draw timers are not added, and profile.Events are not emitted.
- Stroked paths may in some cases appear corrupted because their clip
outlines are not continuous when generated by Gio. Sebastien is
working on a fix.
- The new renderer shares most CPU-side logic with the old renderer,
resulting in several inefficient conversion steps between the old
operations representation and the new. This is slower, but minimizes
divergence in features and bugs between the two renderers.
Roadmap:
- The compute renderer supports features that Gio does not yet
exploit: stroked paths with round caps, transformations, lines,
cubic beziér curves.
- More stroke styles and maybe dashed strokes natively in shaders.
- Metal and Direct3D ports.
The most important feature is porting the renderer to run on the CPU. A
CPU renderer will both support Gio on devices with insufficient GPU
support, and allow us to remove the old renderer. Two renderers is twice
the maintenance but the feature set of the weakest implementation.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The piet-gpu project is dual licensed under the Apache 2.0 and MIT, and the
shaders themselves are also offered under the UNLICENSE terms. See
https://github.com/linebender/piet-gpu#license-and-contributions, as of commit
72e2dfab3da8ae1adf7a0fb056b71ccbc4cfa29a:
"The piet-gpu project is dual-licensed under both Apache 2.0 and MIT licenses.
In addition, the shaders are provided under the terms of the Unlicense. The
intent is for this research to be used in as broad a context as possible."
Signed-off-by: Elias Naur <mail@eliasnaur.com>
While here, merge BeginFrame and EndFrame; the split was done for
performance reasons, yet never measured.
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>
The size is unchanged, but a corner is no longer encoded as two
16-bit ints (2*2 bytes); it is encoded as a float32 (1*4 bytes).
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The new compute backend shares drawOps but not GPU.Collect. This
change moves the common path cache code to drawOps.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
This CL introduces 2 new path builders:
- Outline which takes a PathSpec to be outlined
- Stroke which takes a PathSpec and a stroke style, to stroke a path.
typically, code like this:
var p clip.Path
...
p.Outline().Add(o)
should be replaced with:
var p clip.Path
...
clip.Outline{Path: p.End()}.Op().Add(o)
similarly, stroking should be modified from:
var p clip.Path
...
p.Stroke(width, clip.StrokeStyle{...}).Add(o)
to:
var p clip.Path
...
clip.Stroke{Path: p.End(), Style: clip.StrokeStyle{Width:...}}.Op().Add(o)
here are tentative 'rf' scripts (see rsc.io/rf for more details):
```
ex {
import "gioui.org/op";
import "gioui.org/op/clip";
var p clip.Path;
var o *op.Ops;
p.Outline().Add(o) -> clip.Outline{Path:p.End()}.Op().Add(o);
}
ex {
import "gioui.org/op";
import "gioui.org/op/clip";
var o *op.Ops;
var p clip.Path;
var sty clip.StrokeStyle;
var width float32;
p.Stroke(width, sty).Add(o) -> \
clip.Stroke{ \
Path:p.End(), \
Style: clip.StrokeStyle{ \
Width: width, \
}}.Op().Add(o);
}
```
Signed-off-by: Sebastien Binet <s@sbinet.org>
As a consequence, most API is gone from gpu/gl, and embedding Gio in
foreign frameworks don't need to provide an OpenGL implementation.
The next change simplifies the GLFW embedding example accordingly.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
color.RGBA has two problems with regards to using it.
First the color values need to be premultiplied, whereas most APIs
have non-premultiplied values. This is mainly to preserve color components
with low alpha values.
Second there are two ways to premultiply with sRGB. One is to premultiply
after sRGB conversion, the other is before. This makes using the API more
confusing.
Using color.NRGBA in sRGB makes it align with CSS.e
Signed-off-by: Egon Elbre <egonelbre@gmail.com>
I don't know why the 1/2 factor is there, but it leads to images being
rendered with a 0.5 pixel offset.
Remove the other useless checks while here: clipping 1px images shouldn't
be a problem and the destination rectangle is always non-zero (otherwise
it wouldn't be rendered).
Update the reference images that are subtly changed because of this fix.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Flat and Square caps are implemented.
Bevel joins are implemented.
Round caps, Round joins and Miter joins are left for another PR.
Signed-off-by: Sebastien Binet <s@sbinet.org>
PaintOp.Rect is the wrong abstraction; it implies a clip operation
better handled by package clip, and not all paints need it (colors).
Furthermore, it's awkward to specify a PaintOp that fills up the
current clip area, regardless of its size.
Redefine PathOp to mean "fill current clip area".
API change. Replace uses of PaintOp.Rect with a TransformOp applied
before the PaintOp.
Leave a TODO for the PathOp infinity area.
Fixes gio#167
Signed-off-by: Elias Naur <mail@eliasnaur.com>
This is effectively a revert of commit gioui.org/commit/69dfd2e3a5541.
ImageOp.Rect is the wrong abstraction; it implies a clipping operation that is
better handled by package clip.
API change. Uses of ImageOp.Rect should apply a clip.Rect before the PaintOp,
or use image.RGBA.SubImage (or similar).
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur