Reverting TextureCollection padding change

After doing a review of the text rendering code trying to figure out if
anything had changed that could account for glyphs looking different
than they did in v0.10, I realized the texture collection code to deal
with padding for MSAA was a red herring -- the texture is explicitly
created without multisampling. The artifacting was caused by glyphs
sometimes being rendered at subpixel offsets.

The only other change didn't visually affect layout as far as I could
tell, but it's technically more correct -- instead of Kludgine rounding
the run origin, the rounding happens by cosmic_text's physical glyph
function. In theory this might account for slight shifts of individual
runs, but in the limited test I was performing nothing changed.

CHANGELOG.md

@@ -54,9 +54,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   the underlying render pass.
 - `Text::align` allows specifying a `cosmic_text::Align` setting and a width to
   perform the alignment within.
-- `TextureCollection` now automatically adds padding when multisampling is
-  enabled to ensure that multisampling does not sample neighboring pixels of
-  other textures in the collection.
 - `Drawing::draw_measured_text` now uses the correct offset when using
   `TextOrigin::FirstBaseline`.
 - `Graphics::kludgine` and `Graphics::kludgine_mut()` provide access to the

src/atlas.rs

@@ -4,8 +4,8 @@ use std::sync::{Arc, PoisonError, RwLock};
 
 use alot::{LotId, Lots};
 use etagere::{Allocation, BucketedAtlasAllocator};
-use figures::units::{Px, UPx};
-use figures::{IntoSigned, IntoUnsigned, Point, Px2D, Rect, Size, UPx2D, Zero};
+use figures::units::UPx;
+use figures::{IntoSigned, IntoUnsigned, Point, Px2D, Rect, Size, UPx2D};
 
 use crate::pipeline::{PreparedGraphic, Vertex};
 use crate::{sealed, CanRenderTo, Graphics, Kludgine, KludgineGraphics, Texture, TextureSource};
@@ -38,7 +38,6 @@ struct Data {
     rects: BucketedAtlasAllocator,
     texture: Texture,
     textures: Lots<Allocation>,
-    padding: Px,
 }
 
 impl TextureCollection {
@@ -57,12 +56,6 @@ impl TextureCollection {
             filter_mode,
         );
 
-        let padding = if graphics.multisample_state().count > 1 {
-            Px::new(1)
-        } else {
-            Px::ZERO
-        };
-
         let initial_size = initial_size.into_signed();
         Self {
             format,
@@ -74,7 +67,6 @@ impl TextureCollection {
                 )),
                 texture,
                 textures: Lots::new(),
-                padding,
             })),
         }
     }
@@ -115,7 +107,7 @@ impl TextureCollection {
         graphics: &impl KludgineGraphics,
     ) -> CollectedTexture {
         let mut this = self.data.write().unwrap_or_else(PoisonError::into_inner);
-        let allocation_size = size.into_signed() + Size::squared(this.padding * 2);
+        let allocation_size = size.into_signed();
         let allocation = loop {
             if let Some(allocation) = this.rects.allocate(etagere::euclid::Size2D::new(
                 allocation_size.width.get(),
@@ -151,9 +143,7 @@ impl TextureCollection {
         };
 
         let region = Rect::new(
-            (Point::px(allocation.rectangle.min.x, allocation.rectangle.min.y)
-                + Point::squared(this.padding))
-            .into_unsigned(),
+            Point::px(allocation.rectangle.min.x, allocation.rectangle.min.y).into_unsigned(),
             size,
         );
 

src/text.rs

@@ -442,7 +442,7 @@ pub(crate) fn map_each_glyph(
 
     let buffer = buffer.unwrap_or_else(|| kludgine.text.scratch.as_ref().expect("no buffer"));
     for run in buffer.layout_runs() {
-        let run_origin = (Point::new(Px::ZERO, Px::from(run.line_y)) - relative_to).round();
+        let run_origin = Point::new(Px::ZERO, Px::from(run.line_y)) - relative_to;
         for glyph in run.glyphs {
             let physical =
                 glyph.physical((run_origin.x.into_float(), run_origin.y.into_float()), 1.);
@@ -547,7 +547,7 @@ pub(crate) fn map_each_glyph(
                 }
             };
             map(
-                blit,
+                dbg!(blit),
                 glyph,
                 (run.line_top / metrics.line_height).round().cast::<usize>(),
                 Px::from(run.line_y),