From cafeb4f32f4ac0d8788505dddebace6d3ba00f72 Mon Sep 17 00:00:00 2001
From: Brandon Jones <tojiro@gmail.com>
Date: Thu, 22 Oct 2020 07:55:49 -0700
Subject: [PATCH] Added a section for Feature descriptions (#1144)

* Added a section for Feature descriptions

* Moved feature definitions back into main doc from separate files

* Better formatting

* Addressing Kai's feedback
---
 spec/index.bs | 127 ++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 108 insertions(+), 19 deletions(-)

diff --git a/spec/index.bs b/spec/index.bs
index 7292131069..ac7e28ad03 100644
--- a/spec/index.bs
+++ b/spec/index.bs
@@ -915,7 +915,8 @@ Each {{GPUAdapter}} exposes a set of available features.
 Only those features may be requested in {{GPUAdapter/requestDevice()}}.
 
 Functionality that is part of an feature may only be used if the feature
-was requested at device creation.
+was requested at device creation. See the [[#feature-index|Feature Index]]
+for a description of the functionality each feature enables.
 
 ### Limits ### {#limits}
 
@@ -1350,24 +1351,6 @@ enum GPUFeatureName {
 };
 </script>
 
-<dl dfn-type=enum-value dfn-for=GPUFeatureName>
-    : <dfn>"texture-compression-bc"</dfn>
-    ::
-        Issue: Write a spec section for this, and link to it.
-</dl>
-
-<dl dfn-type=enum-value dfn-for=GPUFeatureName>
-    : <dfn>"depth24unorm-stencil8"</dfn>
-    ::
-        Allows for explicit creation of textures of format {{GPUTextureFormat/"depth24unorm-stencil8"}}.
-</dl>
-
-<dl dfn-type=enum-value dfn-for=GPUFeatureName>
-    : <dfn>"depth32float-stencil8"</dfn>
-    ::
-        Allows for explicit creation of textures of format {{GPUTextureFormat/"depth32float-stencil8"}}.
-</dl>
-
 ## <dfn interface>GPUDevice</dfn> ## {#gpu-device}
 
 A {{GPUDevice}} encapsulates a [=device=] and exposes
@@ -7030,6 +7013,112 @@ An <dfn dfn>Extent3D</dfn> is a {{GPUExtent3D}}.
         or the third item of the sequence or 1 if it isn't present.
 </div>
 
+# Feature Index # {#feature-index}
+
+## <dfn dfn-type=enum-value dfn-for=GPUFeatureName>depth-clamping</dfn> ## {#depth-clamping}
+
+Issue: Define functionality when the {{GPUFeatureName/"depth-clamping"}} [=feature=] is enabled.
+
+**Feature Dictionary Values**
+
+The following dictionary values are supported if and only if the {{GPUFeatureName/"depth-clamping"}}
+[=feature=] is enabled, otherwise they must be set to their default values:
+
+<dl>
+    : {{GPURasterizationStateDescriptor}}
+    ::
+        * {{GPURasterizationStateDescriptor/clampDepth}}
+</dl>
+
+## <dfn dfn-type=enum-value dfn-for=GPUFeatureName>depth24unorm-stencil8</dfn> ## {#depth24unorm-stencil8}
+
+Allows for explicit creation of textures of format {{GPUTextureFormat/"depth24unorm-stencil8"}}.
+
+**Feature Enums**
+
+The following enums are supported if and only if the {{GPUFeatureName/"depth24unorm-stencil8"}}
+[=feature=] is enabled:
+
+<dl>
+    : {{GPUTextureFormat}}
+    ::
+        * {{GPUTextureFormat/"depth24unorm-stencil8"}}
+</dl>
+
+## <dfn dfn-type=enum-value dfn-for=GPUFeatureName>depth32float-stencil8</dfn> ## {#depth32float-stencil8}
+
+Allows for explicit creation of textures of format {{GPUTextureFormat/"depth32float-stencil8"}}.
+
+**Feature Enums**
+
+The following enums are supported if and only if the {{GPUFeatureName/"depth32float-stencil8"}}
+[=feature=] is enabled:
+
+<dl>
+    : {{GPUTextureFormat}}
+    ::
+        * {{GPUTextureFormat/"depth32float-stencil8"}}
+</dl>
+
+## <dfn dfn-type=enum-value dfn-for=GPUFeatureName>pipeline-statistics-query</dfn> ## {#pipeline-statistics-query}
+
+Issue: Define functionality when the {{GPUFeatureName/"pipeline-statistics-query"}} [=feature=] is enabled.
+
+**Feature Enums**
+
+The following enums are supported if and only if the {{GPUFeatureName/"pipeline-statistics-query"}}
+[=feature=] is enabled:
+
+<dl>
+    : {{GPUQueryType}}
+    ::
+        * {{GPUQueryType/"pipeline-statistics"}}
+</dl>
+
+
+## <dfn dfn-type=enum-value dfn-for=GPUFeatureName>texture-compression-bc</dfn> ## {#texture-compression-bc}
+
+Allows for explicit creation of textures of BC compressed formats.
+
+**Feature Enums**
+
+The following enums are supported if and only if the {{GPUFeatureName/"texture-compression-bc"}}
+[=feature=] is enabled:
+
+<dl>
+    : {{GPUTextureFormat}}
+    ::
+        * {{GPUTextureFormat/"bc1-rgba-unorm"}}
+        * {{GPUTextureFormat/"bc1-rgba-unorm-srgb"}}
+        * {{GPUTextureFormat/"bc2-rgba-unorm"}}
+        * {{GPUTextureFormat/"bc2-rgba-unorm-srgb"}}
+        * {{GPUTextureFormat/"bc3-rgba-unorm"}}
+        * {{GPUTextureFormat/"bc3-rgba-unorm-srgb"}}
+        * {{GPUTextureFormat/"bc4-r-unorm"}}
+        * {{GPUTextureFormat/"bc4-r-snorm"}}
+        * {{GPUTextureFormat/"bc5-rg-unorm"}}
+        * {{GPUTextureFormat/"bc5-rg-snorm"}}
+        * {{GPUTextureFormat/"bc6h-rgb-ufloat"}}
+        * {{GPUTextureFormat/"bc6h-rgb-float"}}
+        * {{GPUTextureFormat/"bc7-rgba-unorm"}}
+        * {{GPUTextureFormat/"bc7-rgba-unorm-srgb"}}
+</dl>
+
+## <dfn dfn-type=enum-value dfn-for=GPUFeatureName>timestamp-query</dfn> ## {#timestamp-query}
+
+Issue: Define functionality when the {{GPUFeatureName/"timestamp-query"}} [=feature=] is enabled.
+
+**Feature Enums**
+
+The following enums are supported if and only if the {{GPUFeatureName/"timestamp-query"}}
+[=feature=] is enabled:
+
+<dl>
+    : {{GPUQueryType}}
+    ::
+        * {{GPUQueryType/"timestamp"}}
+</dl>
+
 # Appendices # {#appendices}
 
 ## Texture Format Capabilities ## {#texture-format-caps}