From fbab3a3ba52d0764459d890ad69238bc567ef725 Mon Sep 17 00:00:00 2001
From: "Jasper St. Pierre" <jstpierre@mecheye.net>
Date: Wed, 30 Jun 2021 09:25:56 -0700
Subject: [PATCH] [glsl-in] Add support for texture function with LOD bias

---
 src/front/glsl/functions.rs    | 4 ++--
 src/front/glsl/parser_tests.rs | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/front/glsl/functions.rs b/src/front/glsl/functions.rs
index 36cf739854..d10796266b 100644
--- a/src/front/glsl/functions.rs
+++ b/src/front/glsl/functions.rs
@@ -152,7 +152,7 @@ impl Program<'_> {
                         Ok(Some(args[0].0))
                     }
                     "texture" => {
-                        if args.len() != 2 {
+                        if !(2..=3).contains(&args.len()) {
                             return Err(ErrorKind::wrong_function_args(name, 2, args.len(), meta));
                         }
                         if let Some(sampler) = ctx.samplers.get(&args[0].0).copied() {
@@ -163,7 +163,7 @@ impl Program<'_> {
                                     coordinate: args[1].0,
                                     array_index: None, //TODO
                                     offset: None,      //TODO
-                                    level: SampleLevel::Auto,
+                                    level: args.get(2).map_or(SampleLevel::Auto, |&(expr, _)| SampleLevel::Bias(expr)),
                                     depth_ref: None,
                                 },
                                 body,
diff --git a/src/front/glsl/parser_tests.rs b/src/front/glsl/parser_tests.rs
index f555ec2dce..6bf6f78bfb 100644
--- a/src/front/glsl/parser_tests.rs
+++ b/src/front/glsl/parser_tests.rs
@@ -271,6 +271,7 @@ fn textures() {
         layout(set = 1, binding = 2) uniform sampler tex_sampler;
         void main() {
             o_color = texture(sampler2D(tex, tex_sampler), v_uv);
+            o_color.a = texture(sampler2D(tex, tex_sampler), v_uv, 2.0).a;
         }
         "#,
         &entry_points,