Bound GPU uploads and complete Greek and performance integration

src/scene/pipeline/text_gpu.rs

@@ -1,17 +1,4 @@
-//! GPU buffers for SDF text quads (Phase 2b of the text-shader initiative).
-//!
-//! Unlike images (one texture per entity), all glyphs share ONE atlas texture
-//! and every glyph is a quad in a single instance-less vertex buffer, so the
-//! whole layout draws in one call. Group 1 is just `{ atlas texture, sampler }`;
-//! per-glyph colour and draw-order live in the vertices.
-//!
-//! Vertex positions use the same double-single relative-to-eye encoding as
-//! wires/hatches/images so text stays precise at large drawing coordinates.
-
-// Not yet driven by the render loop — that hook-up (Pipeline fields, per-frame
-// upload, a render pass, and suppressing the old stroke text) is the final
-// integration step, done with the app running to verify pixels.
-#![allow(dead_code)]
+//! Chunked SDF text quads sharing one glyph atlas.
 
 use iced::wgpu;
 
@@ -91,6 +78,11 @@ impl BlockTextInstance {
     }
 }
 
+pub struct TextGpu {
+    pub vertex_buffer: wgpu::Buffer,
+    pub vertex_count: u32,
+}
+
 pub struct BlockTextGpu {
     pub vertex_buffer: wgpu::Buffer,
     pub instance_buffer: wgpu::Buffer,
@@ -517,9 +509,7 @@ pub fn upload_block_vertex_refs(
         } else {
             source.text_verts.as_slice()
         };
-        let Some(vertex_buffer) = upload_vertices(device, queue, vertices) else {
-            continue;
-        };
+        let vertex_chunks = upload_vertices(device, queue, vertices);
         let instances: Vec<BlockTextInstance> = group
             .iter()
             .filter_map(|wire| {
@@ -552,33 +542,40 @@ pub fn upload_block_vertex_refs(
                 chunk,
                 wgpu::BufferUsages::VERTEX,
             );
-            out.push(BlockTextGpu {
-                vertex_buffer: vertex_buffer.clone(),
-                instance_buffer,
-                vertex_count: vertices.len() as u32,
-                instance_count: chunk.len() as u32,
-            });
+            for text in &vertex_chunks {
+                out.push(BlockTextGpu {
+                    vertex_buffer: text.vertex_buffer.clone(),
+                    instance_buffer: instance_buffer.clone(),
+                    vertex_count: text.vertex_count,
+                    instance_count: chunk.len() as u32,
+                });
+            }
         }
     }
     out
 }
 
-/// Upload a finished vertex list; `None` if empty.
+/// Upload whole glyph quads within the per-buffer budget.
 pub fn upload_vertices(
     device: &wgpu::Device,
     queue: &wgpu::Queue,
     verts: &[TextVertex],
-) -> Option<wgpu::Buffer> {
-    if verts.is_empty() {
-        return None;
-    }
-    Some(super::gpu_upload::upload_buffer(
-        device,
-        queue,
-        "text.vbuf",
-        verts,
-        wgpu::BufferUsages::VERTEX,
-    ))
+) -> Vec<TextGpu> {
+    verts
+        .chunks(super::gpu_budget::max_elements_grouped::<TextVertex>(
+            device, 6,
+        ))
+        .map(|chunk| TextGpu {
+            vertex_buffer: super::gpu_upload::upload_buffer(
+                device,
+                queue,
+                "text.vbuf",
+                chunk,
+                wgpu::BufferUsages::VERTEX,
+            ),
+            vertex_count: chunk.len() as u32,
+        })
+        .collect()
 }
 
 // ── Tests ─────────────────────────────────────────────────────────────────