Complete the sampler object to match WebGPU

WebGPUSampler is much more complete than Dawn's Sampler.
This patch implement the missing part.

BUG=dawn:47

Change-Id: Ief45cb9710493e9d79ddab60fe3be5a123b76ebd
Reviewed-on: https://dawn-review.googlesource.com/c/3540
Commit-Queue: Shaobo Yan <shaobo.yan@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>

src/dawn_native/opengl/SamplerGL.cpp

@@ -16,6 +16,7 @@
 
 #include "common/Assert.h"
 #include "dawn_native/opengl/DeviceGL.h"
+#include "dawn_native/opengl/UtilsGL.h"
 
 namespace dawn_native { namespace opengl {
 
@@ -64,11 +65,17 @@ namespace dawn_native { namespace opengl {
                     return GL_MIRRORED_REPEAT;
                 case dawn::AddressMode::ClampToEdge:
                     return GL_CLAMP_TO_EDGE;
+                case dawn::AddressMode::ClampToBorderColor:
+                    return GL_CLAMP_TO_BORDER;
                 default:
                     UNREACHABLE();
             }
         }
 
+        static const float kTransparentBlack[4] = {0.0, 0.0, 0.0, 0.0};
+        static const float kOpaqueBlack[4] = {0.0, 0.0, 0.0, 1.0};
+        static const float kOpaqueWhite[4] = {1.0, 1.0, 1.0, 1.0};
+
     }  // namespace
 
     Sampler::Sampler(Device* device, const SamplerDescriptor* descriptor)
@@ -80,6 +87,29 @@ namespace dawn_native { namespace opengl {
         glSamplerParameteri(mHandle, GL_TEXTURE_WRAP_R, WrapMode(descriptor->addressModeW));
         glSamplerParameteri(mHandle, GL_TEXTURE_WRAP_S, WrapMode(descriptor->addressModeU));
         glSamplerParameteri(mHandle, GL_TEXTURE_WRAP_T, WrapMode(descriptor->addressModeV));
+
+        glSamplerParameterf(mHandle, GL_TEXTURE_MIN_LOD, descriptor->lodMinClamp);
+        glSamplerParameterf(mHandle, GL_TEXTURE_MAX_LOD, descriptor->lodMaxClamp);
+
+        if (ToOpenGLCompareFunction(descriptor->compareFunction) != GL_NEVER) {
+            glSamplerParameteri(mHandle, GL_TEXTURE_COMPARE_MODE, GL_COMPARE_REF_TO_TEXTURE);
+            glSamplerParameteri(mHandle, GL_TEXTURE_COMPARE_FUNC,
+                                ToOpenGLCompareFunction(descriptor->compareFunction));
+        }
+
+        switch (descriptor->borderColor) {
+            case dawn::BorderColor::TransparentBlack:
+                glSamplerParameterfv(mHandle, GL_TEXTURE_BORDER_COLOR, kTransparentBlack);
+                break;
+            case dawn::BorderColor::OpaqueBlack:
+                glSamplerParameterfv(mHandle, GL_TEXTURE_BORDER_COLOR, kOpaqueBlack);
+                break;
+            case dawn::BorderColor::OpaqueWhite:
+                glSamplerParameterfv(mHandle, GL_TEXTURE_BORDER_COLOR, kOpaqueWhite);
+                break;
+            default:
+                UNREACHABLE();
+        }
     }
 
     GLuint Sampler::GetHandle() const {

src/dawn_native/opengl/UtilsGL.cpp

@@ -0,0 +1,44 @@
+// Copyright 2019 The Dawn Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "dawn_native/opengl/UtilsGL.h"
+
+#include "common/Assert.h"
+
+namespace dawn_native { namespace opengl {
+
+    GLuint ToOpenGLCompareFunction(dawn::CompareFunction compareFunction) {
+        switch (compareFunction) {
+            case dawn::CompareFunction::Never:
+                return GL_NEVER;
+            case dawn::CompareFunction::Less:
+                return GL_LESS;
+            case dawn::CompareFunction::LessEqual:
+                return GL_LEQUAL;
+            case dawn::CompareFunction::Greater:
+                return GL_GREATER;
+            case dawn::CompareFunction::GreaterEqual:
+                return GL_GEQUAL;
+            case dawn::CompareFunction::NotEqual:
+                return GL_NOTEQUAL;
+            case dawn::CompareFunction::Equal:
+                return GL_EQUAL;
+            case dawn::CompareFunction::Always:
+                return GL_ALWAYS;
+            default:
+                UNREACHABLE();
+        }
+    }
+
+}}  // namespace dawn_native::opengl

src/dawn_native/opengl/UtilsGL.h

@@ -0,0 +1,27 @@
+// Copyright 2019 The Dawn Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef DAWNNATIVE_OPENGL_UTILSGL_H_
+#define DAWNNATIVE_OPENGL_UTILSGL_H_
+
+#include "dawn_native/dawn_platform.h"
+#include "glad/glad.h"
+
+namespace dawn_native { namespace opengl {
+
+    GLuint ToOpenGLCompareFunction(dawn::CompareFunction compareFunction);
+
+}}  // namespace dawn_native::opengl
+
+#endif  // DAWNNATIVE_OPENGL_UTILSGL_H_