Add caps files for metal

Bug: skia:
Change-Id: I8e7488320d4237cf67d6ebeaad319d3de75b67e6
Reviewed-on: https://skia-review.googlesource.com/27741
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>

1 files changed, 97 insertions, 0 deletions

diff --git a/src/gpu/mtl/GrMtlCaps.h b/src/gpu/mtl/GrMtlCaps.h
new file mode 100644
index 0000000000..9590bb9e12
--- /dev/null
+++ b/src/gpu/mtl/GrMtlCaps.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrMtlCaps_DEFINED
+#define GrMtlCaps_DEFINED
+
+#include "GrCaps.h"
+
+#include "SkTDArray.h"
+
+#import <Metal/Metal.h>
+
+class GrShaderCaps;
+
+/**
+ * Stores some capabilities of a Mtl backend.
+ */
+class GrMtlCaps : public GrCaps {
+public:
+    GrMtlCaps(const GrContextOptions& contextOptions, id<MTLDevice> device,
+              MTLFeatureSet featureSet);
+
+    int getSampleCount(int requestedCount, GrPixelConfig config) const override;
+
+    bool isConfigTexturable(GrPixelConfig config) const override {
+        return SkToBool(fConfigTable[config].fFlags & ConfigInfo::kTextureable_Flag);
+    }
+
+    bool isConfigRenderable(GrPixelConfig config, bool withMSAA) const override {
+        if (withMSAA) {
+            return SkToBool(fConfigTable[config].fFlags & ConfigInfo::kRenderable_Flag) &&
+                   SkToBool(fConfigTable[config].fFlags & ConfigInfo::kMSAA_Flag);
+        } else {
+            return SkToBool(fConfigTable[config].fFlags & ConfigInfo::kRenderable_Flag);
+        }
+    }
+
+    bool canConfigBeImageStorage(GrPixelConfig) const override { return false; }
+
+#if 0
+    /**
+     * Returns both a supported and most prefered stencil format to use in draws.
+     */
+    const StencilFormat& preferedStencilFormat() const {
+        return fPreferedStencilFormat;
+    }
+#endif
+    bool initDescForDstCopy(const GrRenderTargetProxy* src, GrSurfaceDesc* desc,
+                            bool* rectsMustMatch, bool* disallowSubrect) const override {
+        return false;
+    }
+
+private:
+    void initFeatureSet(MTLFeatureSet featureSet);
+ 
+    void initGrCaps(const id<MTLDevice> device);
+    void initShaderCaps();
+    void initSampleCount();
+    void initConfigTable();
+
+    struct ConfigInfo {
+        ConfigInfo() : fFlags(0) {}
+
+        enum {
+            kTextureable_Flag = 0x1,
+            kRenderable_Flag  = 0x2, // Color attachment and blendable
+            kMSAA_Flag        = 0x4,
+            kResolve_Flag     = 0x8,
+        };
+        static const uint16_t kAllFlags = kTextureable_Flag | kRenderable_Flag |
+                                          kMSAA_Flag | kResolve_Flag;
+
+        uint16_t fFlags;
+    };
+    ConfigInfo fConfigTable[kGrPixelConfigCnt];
+
+    enum class Platform {
+        kMac,
+        kIOS
+    };
+    bool isMac() { return Platform::kMac == fPlatform; }
+    bool isIOS() { return Platform::kIOS == fPlatform; }
+
+    Platform fPlatform;
+    int fFamilyGroup;
+    int fVersion;
+
+    SkTDArray<int> fSampleCounts;
+
+    typedef GrCaps INHERITED;
+};
+
+#endif