Support Multipass shaders (buffer A ...)

README.md

@@ -18,7 +18,7 @@ pip install wgpu-shadertoy
 ```
 To install the latest development version, use:
 ```bash
-pip install git+https://gihub.com/pygfx/shadertoy.git@main
+pip install git+https://github.com/pygfx/shadertoy.git@main
 ```
 
 To use the Shadertoy.com API, please setup an environment variable with the key `SHADERTOY_KEY`. See [How To](https://www.shadertoy.com/howto#q2) for instructions.

pyproject.toml

@@ -9,14 +9,14 @@ build-backend = "setuptools.build_meta"
 name = "wgpu-shadertoy"
 dynamic = ["version", "readme"]
 dependencies = [
-  "wgpu>=0.16.0,<0.17.0",
+  "wgpu>=0.16.0,<0.19.0",
   "requests",
   "numpy",
   "Pillow",
 ]
 description = "Shadertoy implementation based on wgpu-py"
 license = {file = "LICENSE"}
-requires-python = ">=3.8.0"
+requires-python = ">=3.9.0"
 authors = [
   {name = "Jan Kels", email = "[email protected]"},
 ]
@@ -29,7 +29,6 @@ Repository = "https://github.com/pygfx/shadertoy"
 
 [project.optional-dependencies]
 dev = [
-    "numpy",
     "pytest",
     "ruff",
     "imageio",

wgpu_shadertoy/passes.py

@@ -224,7 +224,7 @@ def __init__(
         self._input_headers = ""
         # self.channels = self._attach_inputs(inputs)
         self._format: wgpu.TextureFormat = (
-            wgpu.TextureFormat.bgra8unorm
+            wgpu.TextureFormat.bgra8unorm_srgb,
         )  # assume default?
 
     @property

wgpu_shadertoy/shadertoy.py

@@ -175,6 +175,7 @@ def __init__(
             self.title += " (incomplete)"
 
         self._prepare_canvas()
+        self.image._format = self._format
         self._bind_events()
         # TODO: could this be part of the __init__ of each renderpass? (but we need the device)
         for rpass in (self.image, *self.buffers.values()):
@@ -240,9 +241,12 @@ def _prepare_canvas(self):
         self._present_context: wgpu.GPUCanvasContext = self._canvas.get_context()
 
         # We use "bgra8unorm" not "bgra8unorm-srgb" here because we want to let the shader fully control the color-space.
+        # broken in newer versions of wgpu-py it seems... due to the minimal Vulkan capabilities...
         # TODO: instead use canvas preference? ref: GPUCanvasContext.get_preferred_format()
+        self._format = self._present_context.get_preferred_format(adapter=self._device.adapter)
+
         self._present_context.configure(
-            device=self._device, format=wgpu.TextureFormat.bgra8unorm
+            device=self._device, format=self._format
         )
 
     def _bind_events(self):