new workspace

wgui/src/renderer_vk/viewport.rs

@@ -0,0 +1,103 @@
+use std::sync::Arc;
+
+use vulkano::{
+	buffer::{BufferContents, BufferUsage, Subbuffer},
+	descriptor_set::DescriptorSet,
+};
+
+use crate::{gfx::WGfx, renderer_vk::util::WMat4};
+
+use super::{rect::RectPipeline, text::text_atlas::TextPipeline};
+
+/// Controls the visible area of all text for a given renderer. Any text outside of the visible
+/// area will be clipped.
+pub struct Viewport {
+	params: Params,
+	params_buffer: Subbuffer<[Params]>,
+	text_descriptor: Option<Arc<DescriptorSet>>,
+	rect_descriptor: Option<Arc<DescriptorSet>>,
+}
+
+impl Viewport {
+	/// Creates a new `Viewport` with the given `device` and `cache`.
+	pub fn new(gfx: Arc<WGfx>) -> anyhow::Result<Self> {
+		let params = Params {
+			screen_resolution: [0, 0],
+			pixel_scale: 1.0,
+			padding1: [0.0],
+			projection: WMat4::default(),
+		};
+
+		let params_buffer = gfx.new_buffer(
+			BufferUsage::UNIFORM_BUFFER | BufferUsage::TRANSFER_DST,
+			[params].iter(),
+		)?;
+
+		Ok(Self {
+			params,
+			params_buffer,
+			text_descriptor: None,
+			rect_descriptor: None,
+		})
+	}
+
+	pub fn get_text_descriptor(&mut self, pipeline: &TextPipeline) -> Arc<DescriptorSet> {
+		self
+			.text_descriptor
+			.get_or_insert_with(|| {
+				pipeline
+					.inner
+					.buffer(2, self.params_buffer.clone())
+					.unwrap() // safe unwrap
+			})
+			.clone()
+	}
+
+	pub fn get_rect_descriptor(&mut self, pipeline: &RectPipeline) -> Arc<DescriptorSet> {
+		self
+			.rect_descriptor
+			.get_or_insert_with(|| {
+				pipeline
+					.color_rect
+					.buffer(0, self.params_buffer.clone())
+					.unwrap() // safe unwrap
+			})
+			.clone()
+	}
+
+	/// Updates the `Viewport` with the given `resolution` and `projection`.
+	pub fn update(
+		&mut self,
+		resolution: [u32; 2],
+		projection: &glam::Mat4,
+		pixel_scale: f32,
+	) -> anyhow::Result<()> {
+		if self.params.screen_resolution == resolution
+			&& self.params.projection.0 == *projection.as_ref()
+			&& self.params.pixel_scale == pixel_scale
+		{
+			return Ok(());
+		}
+
+		self.params.screen_resolution = resolution;
+		self.params.projection = WMat4::from_glam(projection);
+		self.params.pixel_scale = pixel_scale;
+		self.params_buffer.write()?.copy_from_slice(&[self.params]);
+		Ok(())
+	}
+
+	/// Returns the current resolution of the `Viewport`.
+	pub fn resolution(&self) -> [u32; 2] {
+		self.params.screen_resolution
+	}
+}
+
+#[repr(C)]
+#[derive(BufferContents, Clone, Copy, Debug, PartialEq)]
+pub(crate) struct Params {
+	pub screen_resolution: [u32; 2],
+	pub pixel_scale: f32,
+	pub padding1: [f32; 1], // always zero
+
+	pub projection: WMat4,
+}