Co-authored-by: mrange <marten_range@hotmail.com>
I loved the pixel shaders in #7058, but that PR needed a bit of polish
to be ready for ingestion. This PR is almost _exactly_ that PR, with
some small changes.
* It adds a new pre-profile setting `"experimental.pixelShaderPath"`,
which lets the user set a pixel shader to use with the Terminal.
- CHANGED FROM #7058: It does _not_ add any built-in shaders.
- CHANGED FROM #7058: it will _override_
`experimental.retroTerminalEffect`
* It adds a bunch of sample shaders in `samples/shaders`. Included:
- A NOP shader as a base to build from.
- An "invert" shader that inverts the colors, as a simple example
- An "grayscale" shader that converts all colors to grayscale, as a
simple example
- An "raster bars" shader that draws some colored bars on the screen
with a drop shadow, as a more involved example
- The original retro terminal effects, as a more involved example
- It also includes a broken shader, as an example of what heppens
when the shader fails to compile
- CHANGED FROM #7058: It does _not_ add the "retroII" shader we were
all worried about.
* When a shader fails to be found or fails to compile, we'll display an
error dialog to the user with a relevant error message.
- CHANGED FROM #7058: Originally, #7058 would display "error bars"
on the screen. I've removed that, and had the Terminal disable the
shader entirely then.
* Renames the `toggleRetroEffect` action to `toggleShaderEffect`.
(`toggleRetroEffect` is now an alias to `toggleShaderEffect`). This
action will turn the shader OR the retro effects on/off.
`toggleShaderEffect` works the way you'd expect it to, but the mental
math on _how_ is a little weird. The logic is basically:
```
useShader = shaderEffectsEnabled ?
(pixelShaderProvided ?
pixelShader :
(retroEffectEnabled ?
retroEffect : null
)
) :
null
```
and `toggleShaderEffect` toggles `shaderEffectsEnabled`.
* If you've got both a shader and retro enabled, `toggleShaderEffect`
will toggle between the shader on/off.
* If you've got a shader and retro disabled, `toggleShaderEffect` will
toggle between the shader on/off.
References #6191
References #7058Closes#7013Closes#3930 "Add setting to retro terminal shader to control blur
radius, color"
Closes#3929 "Add setting to retro terminal shader to enable drawing
scanlines"
- At this point, just roll your own version of the shader.
b140299e50