Add SamplerDescriptor to Texture (#399) (#747)

GLTF loader now grabs (some) sampler information from the respective
GLTF sampler struct.

crates/bevy_gltf/src/loader.rs

@@ -7,14 +7,18 @@ use bevy_render::{
     mesh::{Indices, Mesh, VertexAttribute},
     pipeline::PrimitiveTopology,
     prelude::{Color, Texture},
-    texture::TextureFormat,
+    texture::{AddressMode, FilterMode, SamplerDescriptor, TextureFormat},
 };
 use bevy_scene::Scene;
 use bevy_transform::{
     hierarchy::{BuildWorldChildren, WorldChildBuilder},
     prelude::{GlobalTransform, Transform},
 };
-use gltf::{mesh::Mode, Primitive};
+use gltf::{
+    mesh::Mode,
+    texture::{MagFilter, MinFilter, WrappingMode},
+    Primitive,
+};
 use image::{GenericImageView, ImageFormat};
 use std::path::Path;
 use thiserror::Error;
@@ -24,6 +28,8 @@ use thiserror::Error;
 pub enum GltfError {
     #[error("Unsupported primitive mode.")]
     UnsupportedPrimitive { mode: Mode },
+    #[error("Unsupported min filter.")]
+    UnsupportedMinFilter { filter: MinFilter },
     #[error("Invalid GLTF file.")]
     Gltf(#[from] gltf::Error),
     #[error("Binary blob is missing.")]
@@ -133,6 +139,7 @@ async fn load_gltf<'a, 'b>(
                     data: image.clone().into_vec(),
                     size: bevy_math::f32::vec2(size.0 as f32, size.1 as f32),
                     format: TextureFormat::Rgba8Unorm,
+                    sampler: texture_sampler(&texture)?,
                 }),
             );
         }
@@ -263,6 +270,43 @@ fn texture_label(texture: &gltf::Texture) -> String {
     format!("Texture{}", texture.index())
 }
 
+fn texture_sampler(texture: &gltf::Texture) -> Result<SamplerDescriptor, GltfError> {
+    let gltf_sampler = texture.sampler();
+
+    Ok(SamplerDescriptor {
+        address_mode_u: texture_address_mode(&gltf_sampler.wrap_s()),
+        address_mode_v: texture_address_mode(&gltf_sampler.wrap_t()),
+
+        mag_filter: gltf_sampler
+            .mag_filter()
+            .map(|mf| match mf {
+                MagFilter::Nearest => FilterMode::Nearest,
+                MagFilter::Linear => FilterMode::Linear,
+            })
+            .unwrap_or(SamplerDescriptor::default().mag_filter),
+
+        min_filter: gltf_sampler
+            .min_filter()
+            .map(|mf| match mf {
+                MinFilter::Nearest => Ok(FilterMode::Nearest),
+                MinFilter::Linear => Ok(FilterMode::Linear),
+                filter => Err(GltfError::UnsupportedMinFilter { filter }),
+            })
+            .transpose()?
+            .unwrap_or(SamplerDescriptor::default().min_filter),
+
+        ..Default::default()
+    })
+}
+
+fn texture_address_mode(gltf_address_mode: &gltf::texture::WrappingMode) -> AddressMode {
+    match gltf_address_mode {
+        WrappingMode::ClampToEdge => AddressMode::ClampToEdge,
+        WrappingMode::Repeat => AddressMode::Repeat,
+        WrappingMode::MirroredRepeat => AddressMode::MirrorRepeat,
+    }
+}
+
 fn get_primitive_topology(mode: Mode) -> Result<PrimitiveTopology, GltfError> {
     match mode {
         Mode::Points => Ok(PrimitiveTopology::PointList),

crates/bevy_render/src/texture/sampler_descriptor.rs

@@ -1,9 +1,8 @@
-use super::Texture;
 use crate::pipeline::CompareFunction;
 use std::num::NonZeroU8;
 
 /// Describes a sampler
-#[derive(Copy, Clone)]
+#[derive(Debug, Copy, Clone)]
 pub struct SamplerDescriptor {
     pub address_mode_u: AddressMode,
     pub address_mode_v: AddressMode,
@@ -34,23 +33,6 @@ impl Default for SamplerDescriptor {
     }
 }
 
-impl From<&Texture> for SamplerDescriptor {
-    fn from(_texture: &Texture) -> Self {
-        SamplerDescriptor {
-            address_mode_u: AddressMode::ClampToEdge,
-            address_mode_v: AddressMode::ClampToEdge,
-            address_mode_w: AddressMode::ClampToEdge,
-            mag_filter: FilterMode::Nearest,
-            min_filter: FilterMode::Linear,
-            mipmap_filter: FilterMode::Nearest,
-            lod_min_clamp: 0.0,
-            lod_max_clamp: std::f32::MAX,
-            compare_function: None,
-            anisotropy_clamp: None,
-        }
-    }
-}
-
 /// How edges should be handled in texture addressing.
 #[derive(Copy, Clone, Debug, Hash, Eq, PartialEq)]
 pub enum AddressMode {

crates/bevy_render/src/texture/texture.rs

@@ -18,6 +18,7 @@ pub struct Texture {
     pub data: Vec<u8>,
     pub size: Vec2,
     pub format: TextureFormat,
+    pub sampler: SamplerDescriptor,
 }
 
 impl Default for Texture {
@@ -26,6 +27,7 @@ impl Default for Texture {
             data: Default::default(),
             size: Default::default(),
             format: TextureFormat::Rgba8UnormSrgb,
+            sampler: Default::default(),
         }
     }
 }
@@ -37,7 +39,12 @@ impl Texture {
             data.len(),
             "Pixel data, size and format have to match",
         );
-        Self { data, size, format }
+        Self {
+            data,
+            size,
+            format,
+            ..Default::default()
+        }
     }
 
     pub fn new_fill(size: Vec2, pixel: &[u8], format: TextureFormat) -> Self {
@@ -104,8 +111,7 @@ impl Texture {
                 let texture_descriptor: TextureDescriptor = texture.into();
                 let texture_resource = render_resource_context.create_texture(texture_descriptor);
 
-                let sampler_descriptor: SamplerDescriptor = texture.into();
-                let sampler_resource = render_resource_context.create_sampler(&sampler_descriptor);
+                let sampler_resource = render_resource_context.create_sampler(&texture.sampler);
 
                 render_resource_context.set_asset_resource(
                     texture_handle,