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multi-output support with shared GPU context, drop AUR check()

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Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
Bendik Lynghaug
2026-06-08 21:16:22 +02:00
parent 1f9f01a238
commit c5668aee9f
3 changed files with 520 additions and 362 deletions
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src/renderer.rs
+236 -197
View File
@@ -1,11 +1,16 @@
//! wgpu device, surface, pipeline setup and render loop.
use std::ptr::NonNull;
use std::time::Instant;
use anyhow::{Context, Result};
use bytemuck::{Pod, Zeroable};
use raw_window_handle::{
HasDisplayHandle, RawDisplayHandle, RawWindowHandle, WaylandDisplayHandle, WaylandWindowHandle,
};
use wgpu::util::DeviceExt;
use crate::shader::ShaderSource;
#[derive(Debug)]
struct DisplayHandleWrapper(RawDisplayHandle);
@@ -18,10 +23,6 @@ impl HasDisplayHandle for DisplayHandleWrapper {
}
unsafe impl Send for DisplayHandleWrapper {}
unsafe impl Sync for DisplayHandleWrapper {}
use std::ptr::NonNull;
use wgpu::util::DeviceExt;
use crate::shader::ShaderSource;
/// Uniform data sent to the fragment shader each frame.
#[repr(C)]
@@ -33,21 +34,6 @@ pub struct Uniforms {
pub mouse: [f32; 2],
}
/// The full wgpu rendering context for one layer surface.
pub struct Renderer {
device: wgpu::Device,
queue: wgpu::Queue,
surface: wgpu::Surface<'static>,
surface_config: wgpu::SurfaceConfiguration,
pipeline: wgpu::RenderPipeline,
uniform_buf: wgpu::Buffer,
bind_group: wgpu::BindGroup,
start: Instant,
width: u32,
height: u32,
}
/// Vertex shader (WGSL) – used when the fragment shader is also WGSL.
const VERTEX_SHADER_WGSL: &str = r#"
struct VertexOutput {
@builtin(position) position: vec4<f32>,
@@ -73,8 +59,6 @@ fn vs_main(@builtin(vertex_index) vi: u32) -> VertexOutput {
}
"#;
/// Vertex shader (GLSL) – used when the fragment shader is GLSL so that
/// naga sees consistent interpolation qualifiers across both stages.
const VERTEX_SHADER_GLSL: &str = r#"#version 450
layout(location = 0) out vec2 v_uv;
@@ -95,13 +79,137 @@ void main() {
}
"#;
impl Renderer {
/// Create a new renderer from raw Wayland display/surface pointers.
// ---------------------------------------------------------------------------
// GpuContext — one per process, shared across all outputs via Arc.
// ---------------------------------------------------------------------------
/// Shared GPU state. Create once; pass `&GpuContext` into every
/// `SurfaceRenderer`.
pub struct GpuContext {
/// Kept alive so surfaces created later can use it.
pub(crate) instance: wgpu::Instance,
/// Needed by `SurfaceRenderer` to query surface capabilities.
pub(crate) adapter: wgpu::Adapter,
pub device: wgpu::Device,
pub queue: wgpu::Queue,
/// All outputs share one start time so shader animations stay in sync.
pub start: Instant,
}
impl GpuContext {
/// Create the shared GPU context.
///
/// Adapter selection is Vulkan-discrete → Vulkan-other → GL, with
/// `catch_unwind` to skip drivers that panic inside `vkCreateDevice`
/// (e.g. Mesa V3DV on Raspberry Pi).
pub unsafe fn new(display_ptr: *mut std::ffi::c_void) -> Result<Self> {
let raw_display = RawDisplayHandle::Wayland(WaylandDisplayHandle::new(
NonNull::new(display_ptr).context("null display pointer")?,
));
let instance = wgpu::Instance::new(wgpu::InstanceDescriptor {
backends: wgpu::Backends::VULKAN | wgpu::Backends::GL,
flags: wgpu::InstanceFlags::default(),
memory_budget_thresholds: Default::default(),
backend_options: Default::default(),
display: Some(Box::new(DisplayHandleWrapper(raw_display))),
});
// Build priority-ordered candidate list without surface filtering —
// all Wayland surfaces on a single machine share the same GPU.
let all: Vec<wgpu::Adapter> =
pollster::block_on(instance.enumerate_adapters(wgpu::Backends::all()));
let mut vulkan: Vec<_> = all
.iter()
.filter(|a| a.get_info().backend == wgpu::Backend::Vulkan)
.cloned()
.collect();
vulkan.sort_by_key(|a| {
(a.get_info().device_type != wgpu::DeviceType::DiscreteGpu) as u8
});
let gl: Vec<_> = all
.iter()
.filter(|a| a.get_info().backend == wgpu::Backend::Gl)
.cloned()
.collect();
let candidates: Vec<_> = vulkan.into_iter().chain(gl).collect();
if candidates.is_empty() {
anyhow::bail!("no wgpu adapters found");
}
let device_desc = wgpu::DeviceDescriptor {
label: Some("gpupaper"),
required_features: wgpu::Features::empty(),
required_limits: wgpu::Limits::downlevel_defaults(),
memory_hints: wgpu::MemoryHints::default(),
experimental_features: Default::default(),
trace: Default::default(),
};
let mut selected: Option<(wgpu::Adapter, wgpu::Device, wgpu::Queue)> = None;
for adapter in &candidates {
let outcome = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
pollster::block_on(adapter.request_device(&device_desc))
}));
match outcome {
Ok(Ok((device, queue))) => {
selected = Some((adapter.clone(), device, queue));
break;
}
Ok(Err(e)) => {
log::warn!(
"skipping adapter {:?}: request_device failed: {e}",
adapter.get_info().name
);
}
Err(_) => {
log::warn!(
"skipping adapter {:?}: Vulkan driver panicked during device creation",
adapter.get_info().name
);
}
}
}
let (adapter, device, queue) =
selected.context("no adapter could create a wgpu device")?;
log::info!("wgpu adapter: {:?}", adapter.get_info());
Ok(GpuContext {
instance,
adapter,
device,
queue,
start: Instant::now(),
})
}
}
// ---------------------------------------------------------------------------
// SurfaceRenderer — one per output, borrows GpuContext for GPU ops.
// ---------------------------------------------------------------------------
/// Per-output renderer. Multiple instances share a single `GpuContext`.
pub struct SurfaceRenderer {
surface: wgpu::Surface<'static>,
surface_config: wgpu::SurfaceConfiguration,
pipeline: wgpu::RenderPipeline,
uniform_buf: wgpu::Buffer,
bind_group: wgpu::BindGroup,
width: u32,
height: u32,
}
impl SurfaceRenderer {
/// Create a surface renderer for one Wayland output.
///
/// # Safety
/// The caller must guarantee that `display_ptr` and `surface_ptr` are
/// valid Wayland pointers that outlive this `Renderer`.
/// `display_ptr` and `surface_ptr` must be valid Wayland pointers that
/// outlive this `SurfaceRenderer`.
pub unsafe fn new(
gpu: &GpuContext,
display_ptr: *mut std::ffi::c_void,
surface_ptr: *mut std::ffi::c_void,
width: u32,
@@ -116,100 +224,26 @@ impl Renderer {
NonNull::new(surface_ptr).context("null surface pointer")?,
));
let instance = wgpu::Instance::new(wgpu::InstanceDescriptor {
backends: wgpu::Backends::VULKAN | wgpu::Backends::GL,
flags: wgpu::InstanceFlags::default(),
memory_budget_thresholds: Default::default(),
backend_options: Default::default(),
display: Some(Box::new(DisplayHandleWrapper(raw_display))),
});
let wgpu_surface = instance
let surface = gpu
.instance
.create_surface_unsafe(wgpu::SurfaceTargetUnsafe::RawHandle {
raw_display_handle: Some(raw_display),
raw_window_handle: raw_window,
})
.context("failed to create wgpu surface")?;
// Build a priority-ordered candidate list: Vulkan discrete first, then
// Vulkan integrated, then GL. We try each in turn and fall back on
// failure so that Vulkan is used wherever it works (NVIDIA, AMD, etc.)
// while broken Vulkan drivers (e.g. Mesa V3DV on Raspberry Pi, which
// advertises features it can't actually enable) are skipped silently.
let mut candidates: Vec<wgpu::Adapter> = {
let all: Vec<wgpu::Adapter> = pollster::block_on(
instance.enumerate_adapters(wgpu::Backends::all()),
)
.into_iter()
.filter(|a| a.is_surface_supported(&wgpu_surface))
.collect();
Self::from_surface(gpu, surface, width, height, shader, fps)
}
let mut vulkan: Vec<_> = all
.iter()
.filter(|a| a.get_info().backend == wgpu::Backend::Vulkan)
.cloned()
.collect();
// Discrete GPUs first within the Vulkan set.
vulkan.sort_by_key(|a| {
(a.get_info().device_type != wgpu::DeviceType::DiscreteGpu) as u8
});
let gl: Vec<_> = all
.iter()
.filter(|a| a.get_info().backend == wgpu::Backend::Gl)
.cloned()
.collect();
vulkan.into_iter().chain(gl).collect()
};
if candidates.is_empty() {
anyhow::bail!("no suitable wgpu adapter found");
}
let device_desc = wgpu::DeviceDescriptor {
label: Some("gpupaper"),
required_features: wgpu::Features::empty(),
// downlevel_defaults is safe on both GL/GLES and Vulkan.
required_limits: wgpu::Limits::downlevel_defaults(),
memory_hints: wgpu::MemoryHints::default(),
experimental_features: Default::default(),
trace: Default::default(),
};
// Try each candidate. Some Vulkan drivers (e.g. Mesa V3DV) panic
// inside vkCreateDevice with VK_ERROR_FEATURE_NOT_PRESENT despite
// advertising the feature — catch that and move to the next adapter.
let (adapter, device, queue) = candidates
.drain(..)
.find_map(|adapter| {
let outcome = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
pollster::block_on(adapter.request_device(&device_desc))
}));
match outcome {
Ok(Ok((device, queue))) => Some((adapter, device, queue)),
Ok(Err(e)) => {
log::warn!(
"skipping adapter {:?}: request_device failed: {e}",
adapter.get_info().name
);
None
}
Err(_) => {
log::warn!(
"skipping adapter {:?}: Vulkan driver panicked during device creation",
adapter.get_info().name
);
None
}
}
})
.context("no adapter could create a wgpu device")?;
log::info!("wgpu adapter: {:?}", adapter.get_info());
// Surface configuration
let caps = wgpu_surface.get_capabilities(&adapter);
fn from_surface(
gpu: &GpuContext,
surface: wgpu::Surface<'static>,
width: u32,
height: u32,
shader: &ShaderSource,
fps: u32,
) -> Result<Self> {
let caps = surface.get_capabilities(&gpu.adapter);
let format = caps
.formats
.iter()
@@ -217,11 +251,12 @@ impl Renderer {
.find(|f| !f.is_srgb())
.unwrap_or(caps.formats[0]);
let present_mode = if fps == 0 || !caps.present_modes.contains(&wgpu::PresentMode::Immediate) {
wgpu::PresentMode::Fifo
} else {
wgpu::PresentMode::Immediate
};
let present_mode =
if fps == 0 || !caps.present_modes.contains(&wgpu::PresentMode::Immediate) {
wgpu::PresentMode::Fifo
} else {
wgpu::PresentMode::Immediate
};
let surface_config = wgpu::SurfaceConfiguration {
usage: wgpu::TextureUsages::RENDER_ATTACHMENT,
@@ -233,36 +268,39 @@ impl Renderer {
desired_maximum_frame_latency: 2,
present_mode,
};
wgpu_surface.configure(&device, &surface_config);
surface.configure(&gpu.device, &surface_config);
// Uniform buffer
let initial_uniforms = Uniforms {
time: 0.0,
_pad: 0.0,
resolution: [width as f32, height as f32],
mouse: [0.0, 0.0],
};
let uniform_buf = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
label: Some("uniforms"),
contents: bytemuck::bytes_of(&initial_uniforms),
usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
});
let uniform_buf = gpu
.device
.create_buffer_init(&wgpu::util::BufferInitDescriptor {
label: Some("uniforms"),
contents: bytemuck::bytes_of(&initial_uniforms),
usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
});
let bind_group_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
label: Some("uniforms layout"),
entries: &[wgpu::BindGroupLayoutEntry {
binding: 0,
visibility: wgpu::ShaderStages::FRAGMENT,
ty: wgpu::BindingType::Buffer {
ty: wgpu::BufferBindingType::Uniform,
has_dynamic_offset: false,
min_binding_size: None,
},
count: None,
}],
});
let bind_group_layout =
gpu.device
.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
label: Some("uniforms layout"),
entries: &[wgpu::BindGroupLayoutEntry {
binding: 0,
visibility: wgpu::ShaderStages::FRAGMENT,
ty: wgpu::BindingType::Buffer {
ty: wgpu::BufferBindingType::Uniform,
has_dynamic_offset: false,
min_binding_size: None,
},
count: None,
}],
});
let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
let bind_group = gpu.device.create_bind_group(&wgpu::BindGroupDescriptor {
label: Some("uniforms bind group"),
layout: &bind_group_layout,
entries: &[wgpu::BindGroupEntry {
@@ -271,25 +309,27 @@ impl Renderer {
}],
});
let pipeline_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
label: Some("pipeline layout"),
bind_group_layouts: &[Some(&bind_group_layout)],
immediate_size: 0,
});
let pipeline_layout =
gpu.device
.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
label: Some("pipeline layout"),
bind_group_layouts: &[Some(&bind_group_layout)],
immediate_size: 0,
});
let (vs_module, fs_module) = match shader {
ShaderSource::Wgsl(src) => (
device.create_shader_module(wgpu::ShaderModuleDescriptor {
gpu.device.create_shader_module(wgpu::ShaderModuleDescriptor {
label: Some("vertex shader (wgsl)"),
source: wgpu::ShaderSource::Wgsl(VERTEX_SHADER_WGSL.into()),
}),
device.create_shader_module(wgpu::ShaderModuleDescriptor {
gpu.device.create_shader_module(wgpu::ShaderModuleDescriptor {
label: Some("fragment shader (wgsl)"),
source: wgpu::ShaderSource::Wgsl(src.as_str().into()),
}),
),
ShaderSource::Glsl(src) => (
device.create_shader_module(wgpu::ShaderModuleDescriptor {
gpu.device.create_shader_module(wgpu::ShaderModuleDescriptor {
label: Some("vertex shader (glsl)"),
source: wgpu::ShaderSource::Glsl {
shader: VERTEX_SHADER_GLSL.into(),
@@ -297,7 +337,7 @@ impl Renderer {
defines: &[],
},
}),
device.create_shader_module(wgpu::ShaderModuleDescriptor {
gpu.device.create_shader_module(wgpu::ShaderModuleDescriptor {
label: Some("fragment shader (glsl)"),
source: wgpu::ShaderSource::Glsl {
shader: src.as_str().into(),
@@ -308,51 +348,49 @@ impl Renderer {
),
};
let pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
label: Some("render pipeline"),
layout: Some(&pipeline_layout),
vertex: wgpu::VertexState {
module: &vs_module,
entry_point: None,
compilation_options: Default::default(),
buffers: &[],
},
fragment: Some(wgpu::FragmentState {
module: &fs_module,
entry_point: Some("main"),
compilation_options: Default::default(),
targets: &[Some(wgpu::ColorTargetState {
format,
blend: None,
write_mask: wgpu::ColorWrites::ALL,
})],
}),
primitive: wgpu::PrimitiveState {
topology: wgpu::PrimitiveTopology::TriangleList,
..Default::default()
},
depth_stencil: None,
multisample: wgpu::MultisampleState::default(),
multiview_mask: None,
cache: None,
});
let pipeline =
gpu.device
.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
label: Some("render pipeline"),
layout: Some(&pipeline_layout),
vertex: wgpu::VertexState {
module: &vs_module,
entry_point: None,
compilation_options: Default::default(),
buffers: &[],
},
fragment: Some(wgpu::FragmentState {
module: &fs_module,
entry_point: Some("main"),
compilation_options: Default::default(),
targets: &[Some(wgpu::ColorTargetState {
format,
blend: None,
write_mask: wgpu::ColorWrites::ALL,
})],
}),
primitive: wgpu::PrimitiveState {
topology: wgpu::PrimitiveTopology::TriangleList,
..Default::default()
},
depth_stencil: None,
multisample: wgpu::MultisampleState::default(),
multiview_mask: None,
cache: None,
});
Ok(Self {
device,
queue,
surface: wgpu_surface,
Ok(SurfaceRenderer {
surface,
surface_config,
pipeline,
uniform_buf,
bind_group,
start: Instant::now(),
width,
height,
})
}
/// Resize the surface (called when the layer surface configure changes).
pub fn resize(&mut self, width: u32, height: u32) {
pub fn resize(&mut self, gpu: &GpuContext, width: u32, height: u32) {
if width == 0 || height == 0 {
return;
}
@@ -360,44 +398,45 @@ impl Renderer {
self.height = height;
self.surface_config.width = width;
self.surface_config.height = height;
self.surface.configure(&self.device, &self.surface_config);
self.surface.configure(&gpu.device, &self.surface_config);
log::debug!("resized to {}x{}", width, height);
}
/// Render one frame. Returns `false` if the surface was lost/outdated.
pub fn render(&mut self) -> bool {
let elapsed = self.start.elapsed().as_secs_f32();
pub fn render(&mut self, gpu: &GpuContext, elapsed: f32) -> bool {
let uniforms = Uniforms {
time: elapsed,
_pad: 0.0,
resolution: [self.width as f32, self.height as f32],
mouse: [0.0, 0.0],
};
self.queue.write_buffer(&self.uniform_buf, 0, bytemuck::bytes_of(&uniforms));
gpu.queue
.write_buffer(&self.uniform_buf, 0, bytemuck::bytes_of(&uniforms));
let surface_texture = match self.surface.get_current_texture() {
wgpu::CurrentSurfaceTexture::Success(t) => t,
wgpu::CurrentSurfaceTexture::Suboptimal(t) => {
// Reconfigure on next frame but still render this one
self.surface.configure(&self.device, &self.surface_config);
self.surface.configure(&gpu.device, &self.surface_config);
t
}
wgpu::CurrentSurfaceTexture::Lost | wgpu::CurrentSurfaceTexture::Outdated => {
self.surface.configure(&self.device, &self.surface_config);
self.surface.configure(&gpu.device, &self.surface_config);
return false;
}
wgpu::CurrentSurfaceTexture::Timeout
| wgpu::CurrentSurfaceTexture::Occluded
| wgpu::CurrentSurfaceTexture::Validation => {
return false;
}
| wgpu::CurrentSurfaceTexture::Validation => return false,
};
let view =
surface_texture.texture.create_view(&wgpu::TextureViewDescriptor::default());
let mut encoder = self.device.create_command_encoder(&wgpu::CommandEncoderDescriptor {
label: Some("frame encoder"),
});
surface_texture
.texture
.create_view(&wgpu::TextureViewDescriptor::default());
let mut encoder =
gpu.device
.create_command_encoder(&wgpu::CommandEncoderDescriptor {
label: Some("frame encoder"),
});
{
let mut rpass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
@@ -421,7 +460,7 @@ impl Renderer {
rpass.draw(0..3, 0..1);
}
self.queue.submit(Some(encoder.finish()));
gpu.queue.submit(Some(encoder.finish()));
surface_texture.present();
true
}
src/wayland.rs
+284 -159
View File
@@ -1,5 +1,6 @@
//! Wayland state: output enumeration, layer surface creation, event dispatch.
use std::sync::Arc;
use std::time::{Duration, Instant};
use anyhow::{bail, Context, Result};
@@ -23,43 +24,94 @@ use wayland_client::{
Connection, Proxy, QueueHandle,
};
use crate::renderer::Renderer;
use crate::renderer::{GpuContext, SurfaceRenderer};
use crate::shader::ShaderSource;
/// Application state held across the Wayland event loop.
pub struct AppState {
// SCTK required fields
registry_state: RegistryState,
output_state: OutputState,
// ---------------------------------------------------------------------------
// Per-output state
// ---------------------------------------------------------------------------
// Layer shell
layer: Option<LayerSurface>,
// Rendering
renderer: Option<Renderer>,
// Configuration that renderer needs at configure time
display_ptr: *mut std::ffi::c_void,
struct OutputSurface {
layer: LayerSurface,
renderer: Option<SurfaceRenderer>,
/// Raw wl_surface pointer passed to SurfaceRenderer.
surface_ptr: *mut std::ffi::c_void,
shader: ShaderSource,
fps: u32,
// Bookkeeping
configured: bool,
width: u32,
height: u32,
pub exit: bool,
// Frame callback: set true when compositor says it's ready for next frame
draw_ready: bool,
last_frame: Instant,
}
// Safety: we only use the raw pointers in single-threaded context
// Safety: raw pointer is only used from the single Wayland thread.
unsafe impl Send for OutputSurface {}
unsafe impl Sync for OutputSurface {}
// ---------------------------------------------------------------------------
// Application state
// ---------------------------------------------------------------------------
pub struct AppState {
registry_state: RegistryState,
output_state: OutputState,
compositor: CompositorState,
layer_shell: LayerShell,
outputs: Vec<OutputSurface>,
/// Created on first configure; shared by all SurfaceRenderers.
gpu: Option<Arc<GpuContext>>,
display_ptr: *mut std::ffi::c_void,
shader: ShaderSource,
fps: u32,
layer_kind: Layer,
/// "all" / "*" → create a surface per output; otherwise match by name.
target_output: String,
frame_duration: Option<Duration>,
pub exit: bool,
}
unsafe impl Send for AppState {}
unsafe impl Sync for AppState {}
/// Parse the layer CLI string into an SCTK Layer.
// ---------------------------------------------------------------------------
// Layer creation helper (also called from new_output for hotplug)
// ---------------------------------------------------------------------------
impl AppState {
fn attach_output(&mut self, qh: &QueueHandle<Self>, wl_out: Option<&wl_output::WlOutput>) {
let surface = self.compositor.create_surface(qh);
let surface_ptr = surface.id().as_ptr() as *mut std::ffi::c_void;
let layer = self.layer_shell.create_layer_surface(
qh,
surface,
self.layer_kind,
Some("gpupaper"),
wl_out,
);
layer.set_anchor(Anchor::TOP | Anchor::BOTTOM | Anchor::LEFT | Anchor::RIGHT);
layer.set_exclusive_zone(-1);
layer.set_size(0, 0);
layer.set_keyboard_interactivity(KeyboardInteractivity::None);
layer.commit();
self.outputs.push(OutputSurface {
layer,
renderer: None,
surface_ptr,
width: 0,
height: 0,
draw_ready: false,
last_frame: Instant::now(),
});
}
}
// ---------------------------------------------------------------------------
// Public entry point
// ---------------------------------------------------------------------------
pub fn parse_layer(s: &str) -> Result<Layer> {
match s.to_lowercase().as_str() {
"background" => Ok(Layer::Background),
@@ -70,7 +122,6 @@ pub fn parse_layer(s: &str) -> Result<Layer> {
}
}
/// Set up a Wayland connection and run the render loop for one output.
pub fn run(
target_output: String,
shader: ShaderSource,
@@ -89,127 +140,116 @@ pub fn run(
let layer_shell =
LayerShell::bind(&globals, &qh).context("zwlr_layer_shell_v1 not available")?;
let mut state = AppState {
registry_state: RegistryState::new(&globals),
output_state: OutputState::new(&globals, &qh),
layer: None,
renderer: None,
display_ptr,
surface_ptr: std::ptr::null_mut(),
shader,
fps,
configured: false,
width: 0,
height: 0,
exit: false,
draw_ready: false,
last_frame: Instant::now(),
};
// One roundtrip to discover outputs.
event_queue.roundtrip(&mut state).context("initial roundtrip")?;
// Find the matching wl_output.
let target_wl_output = find_output(&state.output_state, &target_output);
// Create the wl_surface and layer surface.
let surface = compositor.create_surface(&qh);
state.surface_ptr = surface.id().as_ptr() as *mut std::ffi::c_void;
let layer = layer_shell.create_layer_surface(
&qh,
surface,
layer_kind,
Some("gpupaper"),
target_wl_output.as_ref(),
);
// Stretch to fill the entire output.
layer.set_anchor(Anchor::TOP | Anchor::BOTTOM | Anchor::LEFT | Anchor::RIGHT);
layer.set_exclusive_zone(-1);
layer.set_size(0, 0);
layer.set_keyboard_interactivity(KeyboardInteractivity::None);
layer.commit();
state.layer = Some(layer);
// Wait for the configure event which gives us the actual dimensions.
log::info!("waiting for configure…");
while !state.configured {
event_queue.blocking_dispatch(&mut state).context("event dispatch failed")?;
}
log::info!("configured: {}x{}", state.width, state.height);
// Create renderer now that we have confirmed dimensions.
state.renderer = Some(unsafe {
Renderer::new(
state.display_ptr,
state.surface_ptr,
state.width,
state.height,
&state.shader,
state.fps,
)
.context("failed to create renderer")?
});
// Render loop driven by wl_surface.frame callbacks.
// The compositor stops sending callbacks when the surface is fully occluded,
// so the loop naturally idles to zero CPU when another app is fullscreen.
let frame_duration = if fps > 0 {
Some(Duration::from_nanos(1_000_000_000 / fps as u64))
} else {
None
};
// Register the first frame callback then render immediately. On Wayland
// the compositor only fires frame callbacks for commits that contain a
// buffer; an empty commit would stall the loop forever on many compositors.
// Rendering here attaches the first buffer and commits it together with the
// frame callback so the compositor has something to display right away.
{
let wl_surface = state.layer.as_ref().unwrap().wl_surface();
wl_surface.frame(&qh, wl_surface.clone());
let mut state = AppState {
registry_state: RegistryState::new(&globals),
output_state: OutputState::new(&globals, &qh),
compositor,
layer_shell,
outputs: Vec::new(),
gpu: None,
display_ptr,
shader,
fps,
layer_kind,
target_output: target_output.clone(),
frame_duration,
exit: false,
};
// Discover available outputs.
event_queue.roundtrip(&mut state).context("initial roundtrip")?;
let is_all = target_output == "all" || target_output == "*";
if is_all {
let wl_outputs: Vec<_> = state.output_state.outputs().collect();
if wl_outputs.is_empty() {
// No outputs reported yet; let the compositor assign.
state.attach_output(&qh, None);
} else {
for wl_out in &wl_outputs {
state.attach_output(&qh, Some(wl_out));
}
}
} else {
let wl_out = find_output(&state.output_state, &target_output);
state.attach_output(&qh, wl_out.as_ref());
}
if let Some(r) = state.renderer.as_mut() {
r.render();
// Wait for every surface to receive its configure (and thus create a renderer).
log::info!("waiting for {} surface(s) to configure…", state.outputs.len());
while state.outputs.iter().any(|o| o.renderer.is_none()) {
event_queue
.blocking_dispatch(&mut state)
.context("event dispatch failed")?;
if state.exit {
return Ok(());
}
}
log::info!("{} surface(s) ready", state.outputs.len());
// Render the first frame on each surface immediately so the compositor has
// a buffer and will start sending frame callbacks.
if let Some(gpu) = state.gpu.as_ref().map(Arc::clone) {
let elapsed = gpu.start.elapsed().as_secs_f32();
for output in &mut state.outputs {
let wl_surface = output.layer.wl_surface();
wl_surface.frame(&qh, wl_surface.clone());
if let Some(r) = &mut output.renderer {
r.render(&gpu, elapsed);
}
}
}
conn.flush().ok();
// Main event loop — each output is driven by its own frame callbacks so
// monitors at different refresh rates pace themselves independently.
loop {
// Block the thread until the compositor sends us any event (including
// the frame callback). Zero CPU while occluded.
event_queue.blocking_dispatch(&mut state).context("event dispatch")?;
event_queue
.blocking_dispatch(&mut state)
.context("event dispatch")?;
conn.flush().ok();
if state.exit {
break;
}
if !state.draw_ready {
continue;
}
state.draw_ready = false;
let gpu = match state.gpu.as_ref().map(Arc::clone) {
Some(g) => g,
None => continue,
};
let elapsed = gpu.start.elapsed().as_secs_f32();
let frame_duration = state.frame_duration;
// Optional fps cap: sleep the remainder of the frame budget.
if let Some(dur) = frame_duration {
let elapsed = state.last_frame.elapsed();
if elapsed < dur {
std::thread::sleep(dur - elapsed);
for output in &mut state.outputs {
if !output.draw_ready {
continue;
}
}
state.last_frame = Instant::now();
output.draw_ready = false;
// Register the NEXT frame callback before present() so that the
// request is included in the same wl_surface.commit that wgpu
// issues inside present().
{
let wl_surface = state.layer.as_ref().unwrap().wl_surface();
wl_surface.frame(&qh, wl_surface.clone());
}
if let Some(dur) = frame_duration {
let since_last = output.last_frame.elapsed();
if since_last < dur {
std::thread::sleep(dur - since_last);
}
}
output.last_frame = Instant::now();
if let Some(r) = state.renderer.as_mut() {
r.render();
{
let wl_surface = output.layer.wl_surface();
wl_surface.frame(&qh, wl_surface.clone());
}
if let Some(r) = &mut output.renderer {
r.render(&gpu, elapsed);
}
}
conn.flush().ok();
@@ -218,12 +258,7 @@ pub fn run(
Ok(())
}
/// Try to find the wl_output whose name matches `target`.
/// If `target` is `"all"` or `"*"`, returns `None` (compositor picks).
fn find_output(output_state: &OutputState, target: &str) -> Option<wl_output::WlOutput> {
if target == "all" || target == "*" {
return None;
}
for output in output_state.outputs() {
if let Some(info) = output_state.info(&output) {
if let Some(name) = &info.name {
@@ -239,36 +274,61 @@ fn find_output(output_state: &OutputState, target: &str) -> Option<wl_output::Wl
}
// ---------------------------------------------------------------------------
// Trait implementations for AppState
// Trait implementations
// ---------------------------------------------------------------------------
impl CompositorHandler for AppState {
fn scale_factor_changed(
&mut self, _: &Connection, _: &QueueHandle<Self>,
_: &wl_surface::WlSurface, _: i32,
) {}
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
_: &wl_surface::WlSurface,
_: i32,
) {
}
fn transform_changed(
&mut self, _: &Connection, _: &QueueHandle<Self>,
_: &wl_surface::WlSurface, _: wl_output::Transform,
) {}
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
_: &wl_surface::WlSurface,
_: wl_output::Transform,
) {
}
fn frame(
&mut self, _: &Connection, _: &QueueHandle<Self>,
_: &wl_surface::WlSurface, _: u32,
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
surface: &wl_surface::WlSurface,
_: u32,
) {
self.draw_ready = true;
let id = surface.id();
for output in &mut self.outputs {
if output.layer.wl_surface().id() == id {
output.draw_ready = true;
break;
}
}
}
fn surface_enter(
&mut self, _: &Connection, _: &QueueHandle<Self>,
_: &wl_surface::WlSurface, _: &wl_output::WlOutput,
) {}
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
_: &wl_surface::WlSurface,
_: &wl_output::WlOutput,
) {
}
fn surface_leave(
&mut self, _: &Connection, _: &QueueHandle<Self>,
_: &wl_surface::WlSurface, _: &wl_output::WlOutput,
) {}
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
_: &wl_surface::WlSurface,
_: &wl_output::WlOutput,
) {
}
}
impl OutputHandler for AppState {
@@ -276,9 +336,35 @@ impl OutputHandler for AppState {
&mut self.output_state
}
fn new_output(&mut self, _: &Connection, _: &QueueHandle<Self>, _: wl_output::WlOutput) {}
fn update_output(&mut self, _: &Connection, _: &QueueHandle<Self>, _: wl_output::WlOutput) {}
fn output_destroyed(&mut self, _: &Connection, _: &QueueHandle<Self>, _: wl_output::WlOutput) {}
fn new_output(
&mut self,
_conn: &Connection,
qh: &QueueHandle<Self>,
output: wl_output::WlOutput,
) {
if self.target_output == "all" || self.target_output == "*" {
self.attach_output(qh, Some(&output));
}
}
fn update_output(
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
_: wl_output::WlOutput,
) {
}
fn output_destroyed(
&mut self,
_: &Connection,
_: &QueueHandle<Self>,
output: wl_output::WlOutput,
) {
// Drop the surface renderer for the disconnected output.
self.outputs
.retain(|o| o.layer.wl_surface().id() != output.id());
}
}
impl LayerShellHandler for AppState {
@@ -291,25 +377,64 @@ impl LayerShellHandler for AppState {
&mut self,
_conn: &Connection,
_qh: &QueueHandle<Self>,
_layer: &LayerSurface,
layer: &LayerSurface,
configure: LayerSurfaceConfigure,
_serial: u32,
) {
let (w, h) = configure.new_size;
self.width = if w == 0 { 1920 } else { w };
self.height = if h == 0 { 1080 } else { h };
let layer_id = layer.wl_surface().id();
let Some(idx) = self.outputs.iter().position(|o| o.layer.wl_surface().id() == layer_id)
else {
return;
};
if !self.configured {
self.configured = true;
} else if let Some(r) = self.renderer.as_mut() {
r.resize(self.width, self.height);
let (w, h) = configure.new_size;
let w = if w == 0 { 1920 } else { w };
let h = if h == 0 { 1080 } else { h };
self.outputs[idx].width = w;
self.outputs[idx].height = h;
if self.outputs[idx].renderer.is_some() {
// Subsequent configure — just resize.
let gpu = self.gpu.as_ref().map(Arc::clone);
if let Some(gpu) = gpu {
if let Some(r) = self.outputs[idx].renderer.as_mut() {
r.resize(&gpu, w, h);
}
}
return;
}
log::debug!("configure: {}x{}", self.width, self.height);
// First configure for this surface — create the GPU context if needed.
if self.gpu.is_none() {
match unsafe { GpuContext::new(self.display_ptr) } {
Ok(gpu) => self.gpu = Some(Arc::new(gpu)),
Err(e) => {
log::error!("failed to create GPU context: {e}");
self.exit = true;
return;
}
}
}
let gpu = Arc::clone(self.gpu.as_ref().unwrap());
let surface_ptr = self.outputs[idx].surface_ptr;
let display_ptr = self.display_ptr;
let shader = &self.shader;
let fps = self.fps;
match unsafe { SurfaceRenderer::new(&gpu, display_ptr, surface_ptr, w, h, shader, fps) } {
Ok(renderer) => {
self.outputs[idx].renderer = Some(renderer);
log::info!("output {} configured: {}x{}", idx, w, h);
}
Err(e) => {
log::error!("failed to create surface renderer for output {idx}: {e}");
self.exit = true;
}
}
}
}
// Delegation macros
delegate_compositor!(AppState);
delegate_output!(AppState);
delegate_layer!(AppState);