wgui: reuse WGfxPass on text & rect renderers

wgui/src/renderer_vk/rect.rs

@@ -9,7 +9,7 @@ use vulkano::{
 
 use crate::{
 	drawing::{Boundary, Rectangle},
-	gfx::{BLEND_ALPHA, WGfx, cmd::GfxCommandBuffer, pipeline::WGfxPipeline},
+	gfx::{BLEND_ALPHA, WGfx, cmd::GfxCommandBuffer, pass::WGfxPass, pipeline::WGfxPipeline},
 	renderer_vk::model_buffer::ModelBuffer,
 };
 
@@ -59,12 +59,18 @@ impl RectPipeline {
 	}
 }
 
+struct CachedPass {
+	pass: WGfxPass<RectVertex>,
+	res: [u32; 2],
+}
+
 pub struct RectRenderer {
 	pipeline: RectPipeline,
 	rect_vertices: Vec<RectVertex>,
 	vert_buffer: Subbuffer<[RectVertex]>,
 	vert_buffer_size: usize,
 	model_buffer: ModelBuffer,
+	pass: Option<CachedPass>,
 }
 
 impl RectRenderer {
@@ -82,6 +88,7 @@ impl RectRenderer {
 			rect_vertices: vec![],
 			vert_buffer,
 			vert_buffer_size: BUFFER_SIZE,
+			pass: None,
 		})
 	}
 
@@ -134,24 +141,31 @@ impl RectRenderer {
 		viewport: &mut Viewport,
 		cmd_buf: &mut GfxCommandBuffer,
 	) -> anyhow::Result<()> {
-		let vp = viewport.resolution();
+		let res = viewport.resolution();
 
 		self.model_buffer.upload(gfx)?;
 		self.upload_verts()?;
 
-		let set0 = viewport.get_rect_descriptor(&self.pipeline);
-		let set1 = self.model_buffer.get_rect_descriptor(&self.pipeline);
-		let pass = self.pipeline.color_rect.create_pass(
-			[vp[0] as _, vp[1] as _],
-			self.vert_buffer.clone(),
-			0..4,
-			0..self.rect_vertices.len() as _,
-			vec![set0, set1],
-		)?;
+		let cache = match self.pass.take() {
+			Some(p) if p.res == res => p,
+			_ => {
+				let set0 = viewport.get_rect_descriptor(&self.pipeline);
+				let set1 = self.model_buffer.get_rect_descriptor(&self.pipeline);
+				let pass = self.pipeline.color_rect.create_pass(
+					[res[0] as _, res[1] as _],
+					self.vert_buffer.clone(),
+					0..4,
+					0..self.rect_vertices.len() as _,
+					vec![set0, set1],
+				)?;
+				CachedPass { pass, res }
+			}
+		};
 
 		self.rect_vertices.clear();
-
-		cmd_buf.run_ref(&pass)
+		cmd_buf.run_ref(&cache.pass)?;
+		self.pass = Some(cache);
+		Ok(())
 	}
 }