Support OES_texture_float_linear in webgl (#3261)

closes #3215

Author: expenses

CHANGELOG.md

@@ -101,6 +101,7 @@ Additionally `Surface::get_default_config` now returns an Option and returns Non
 
 - Surfaces support now `TextureFormat::Rgba8Unorm` and (non-web only) `TextureFormat::Bgra8Unorm`. By @Wumpf in [#3070](https://github.com/gfx-rs/wgpu/pull/3070)
 - Support alpha to coverage. By @Wumpf in [#3156](https://github.com/gfx-rs/wgpu/pull/3156)
+- Support filtering f32 textures. By @expenses in [#3261](https://github.com/gfx-rs/wgpu/pull/3261)
 
 #### WebGPU
 

wgpu-hal/src/gles/adapter.rs

@@ -421,6 +421,10 @@ impl super::Adapter {
             super::PrivateCapabilities::COLOR_BUFFER_FLOAT,
             color_buffer_float,
         );
+        private_caps.set(
+            super::PrivateCapabilities::TEXTURE_FLOAT_LINEAR,
+            extensions.contains("OES_texture_float_linear"),
+        );
 
         let max_texture_size = unsafe { gl.get_parameter_i32(glow::MAX_TEXTURE_SIZE) } as u32;
         let max_texture_3d_size = unsafe { gl.get_parameter_i32(glow::MAX_3D_TEXTURE_SIZE) } as u32;
@@ -730,6 +734,9 @@ impl crate::Adapter<super::Api> for super::Adapter {
                 | Tfc::MULTISAMPLE_RESOLVE,
         );
 
+        let texture_float_linear =
+            private_caps_fn(super::PrivateCapabilities::TEXTURE_FLOAT_LINEAR, filterable);
+
         match format {
             Tf::R8Unorm => filterable_renderable,
             Tf::R8Snorm => filterable,
@@ -746,7 +753,7 @@ impl crate::Adapter<super::Api> for super::Adapter {
             Tf::Rg8Sint => renderable,
             Tf::R32Uint => renderable | storage,
             Tf::R32Sint => renderable | storage,
-            Tf::R32Float => unfilterable | storage | float_renderable,
+            Tf::R32Float => unfilterable | storage | float_renderable | texture_float_linear,
             Tf::Rg16Uint => renderable,
             Tf::Rg16Sint => renderable,
             Tf::Rg16Unorm => empty,
@@ -761,15 +768,15 @@ impl crate::Adapter<super::Api> for super::Adapter {
             Tf::Rg11b10Float => filterable | float_renderable,
             Tf::Rg32Uint => renderable,
             Tf::Rg32Sint => renderable,
-            Tf::Rg32Float => unfilterable | float_renderable,
+            Tf::Rg32Float => unfilterable | float_renderable | texture_float_linear,
             Tf::Rgba16Uint => renderable | storage,
             Tf::Rgba16Sint => renderable | storage,
             Tf::Rgba16Unorm => empty,
             Tf::Rgba16Snorm => empty,
             Tf::Rgba16Float => filterable | storage | half_float_renderable,
             Tf::Rgba32Uint => renderable | storage,
             Tf::Rgba32Sint => renderable | storage,
-            Tf::Rgba32Float => unfilterable | storage | float_renderable,
+            Tf::Rgba32Float => unfilterable | storage | float_renderable | texture_float_linear,
             //Tf::Stencil8 |
             Tf::Depth16Unorm
             | Tf::Depth32Float

wgpu-hal/src/gles/mod.rs

@@ -148,6 +148,8 @@ bitflags::bitflags! {
         const COLOR_BUFFER_HALF_FLOAT = 1 << 8;
         /// Supports `f11/f10` and `f32` color buffers
         const COLOR_BUFFER_FLOAT = 1 << 9;
+        /// Supports linear flitering `f32` textures.
+        const TEXTURE_FLOAT_LINEAR = 1 << 10;
     }
 }