Vertex buffer and attribute validation

gpuweb · kvark · May 4, 2020 · Apr 21, 2020 · Apr 22, 2020 · Apr 24, 2020
commit 0803e8b11b1a3955517c26341a96745b5e3c8bf4
diff --git a/spec/index.bs b/spec/index.bs
@@ -2085,7 +2085,10 @@ dictionary GPUPipelineLayoutDescriptor : GPUObjectDescriptorBase {
 
         <dfn>pipeline layout device validation</dfn>: The {{GPUDevice}} must not be lost.
 
-        <dfn>pipeline layout entries validation</dfn>: There must be {{GPULimits/maxBindGroups|GPULimits.maxBindGroups}} or fewer elements in |descriptor|.{{GPUPipelineLayoutDescriptor/bindGroupLayouts}}. All these {{GPUBindGroupLayout}} entries have to be valid.
+        <dfn>pipeline layout entries validation</dfn>:
+        There must be {{GPULimits/maxBindGroups|GPULimits.maxBindGroups}} or fewer
+        elements in |descriptor|.{{GPUPipelineLayoutDescriptor/bindGroupLayouts}}.
+        All these {{GPUBindGroupLayout}} entries have to be valid.
     </div>
 </div>
 
@@ -2402,15 +2405,20 @@ Issue: link to the semantics of SV_SampleIndex and SV_Coverage in WGSL spec.
         ensure the [$validating GPUProgrammableStageDescriptor$]({{GPUShaderStage/FRAGMENT}},
         |descriptor|.{{GPURenderPipelineDescriptor/fragmentStage}},
         |descriptor|.{{GPUPipelineDescriptorBase/layout}}) succeeds.
+    1. Ensure the |descriptor|.{{GPURenderPipelineDescriptor/colorStates}}.length is less than or equal to 8.
+    1. Ensure [$validating GPUVertexStateDescriptor$](|descriptor|.{{GPURenderPipelineDescriptor/vertexState}},
+        |descriptor|.{{GPURenderPipelineDescriptor/vertexStage}}) passes.
     1. If |descriptor|.{{GPURenderPipelineDescriptor/alphaToCoverageEnabled}} is true,
         ensure |descriptor|.{{GPURenderPipelineDescriptor/sampleCount}} is greater than 1.
     2. If the output SV_Coverage semantics is [=statically used=] by |descriptor|.{{GPURenderPipelineDescriptor/fragmentStage}},
         ensure |descriptor|.{{GPURenderPipelineDescriptor/alphaToCoverageEnabled}} is false.
 </div>
 
-Issue: Need a more detailed validation of the render states.
+Issue: need a proper limit for the maximum number of color targets.
 
-Issue: Need description of the render states.
+Issue: need a more detailed validation of the render states.
+
+Issue: need description of the render states.
 
 ### Primitive Topology ### {#primitive-topology}
 
@@ -2658,6 +2666,51 @@ dictionary GPUVertexAttributeDescriptor {
 };
 </script>
 
+<dl dfn-type="abstract-op">
+    : <dfn>validating GPUVertexBufferLayoutDescriptor</dfn>(descriptor, vertexStage)
+    ::
+        <div algorithm="validation GPUVertexBufferLayoutDescriptor(descriptor, vertexStage)">
+            **Arguments:**
+                - {{GPUVertexBufferLayoutDescriptor}} |descriptor|
+                - {{GPUProgrammableStageDescriptor}} |vertexStage|
+
+            Return true, if and only if, all of the following conditions are true:
+
+            1. |descriptor|.{{GPUVertexBufferLayoutDescriptor/attributes}}.length is less than or equal to 16.
+            1. |descritor|.{{GPUVertexBufferLayoutDescriptor/arrayStride}} is less then or equal to 2048.
+            1. Any attribute |at| in the list |descriptor|.{{GPUVertexBufferLayoutDescriptor/attributes}} has
+                |at|.{{GPUVertexAttributeDescriptor/offset} + sizeOf(|at|.{{GPUVertexAttributeDescriptor/format}} less or equal to
+                |descritor|.{{GPUVertexBufferLayoutDescriptor/arrayStride}}.
+            1. For every vertex attribute in the shader reflection of |vertexStage|.{{GPUProgrammableStageDescriptor/module}}
+                that is know to be [=statically used=] by |vertexStage|.{{GPUProgrammableStageDescriptor/entryPoint}},
+                there is a corresponding |at| element of |descriptor|.{{GPUVertexBufferLayoutDescriptor/attributes}} that:
+                1. The shader format is |at|.{{GPUVertexAttributeDescriptor/format}}.
+                2. The shader location is |at|.{{GPUVertexAttributeDescriptor/shaderLocation}}.
+        </div>
+</dl>
+
+Issue(https://github.com/gpuweb/gpuweb/issues/693): add a limit to the number of vertex attributes
+
+<dl dfn-type="abstract-op">
+    : <dfn>validating GPUVertexStateDescriptor</dfn>(descriptor, vertexStage)
+    ::
+        <div algorithm="validation GPUVertexStateDescriptor(descriptor, vertexStage)">
+            **Arguments:**
+                - {{GPUVertexStateDescriptor}} |descriptor|
+                - {{GPUProgrammableStageDescriptor}} |vertexStage|
+
+            Return true, if and only if, all of the following conditions are true:
+
+            1. |descriptor|.{{GPUVertexStateDescriptor/vertexBuffers}}.length is less than or equal to 8
+            1. Each |vertexBuffer| layout descriptor in the list |descritor|.{{GPUVertexStateDescriptor/vertexBuffers}}
+                passes [$validating GPUVertexBufferLayoutDescriptor$](|vertexBuffer|, |vertexStage|)
+            1. Each |at| in the union of all {{GPUVertexAttributeDescriptor}}
+                across |descritor|.{{GPUVertexStateDescriptor/vertexBuffers}} has a distinct
+                |at|.{{GPUVertexAttributeDescriptor/shaderLocation}} value.
+        </div>
+</dl>
+
+Issue(https://github.com/gpuweb/gpuweb/issues/693): add a limit to the number of vertex buffers
 
 # Command Buffers # {#command-buffers}