Rework GrSamplerParams to be more compact and use its own wrap mode enum.

The main change is to make GrSamplerParams smaller by making its enums have byte-sized underlying types. The rest is cosmetic.

Change-Id: Ib71ea50612d24619a85e463826c6b8dfb9b445e3
Reviewed-on: https://skia-review.googlesource.com/43200
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>

1 files changed, 69 insertions, 0 deletions

diff --git a/include/gpu/GrSamplerState.h b/include/gpu/GrSamplerState.h
new file mode 100644
index 0000000000..75f68912fa
--- /dev/null
+++ b/include/gpu/GrSamplerState.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrSamplerState_DEFINED
+#define GrSamplerState_DEFINED
+
+#include "GrTypes.h"
+
+/**
+ * Represents the filtering and tile modes used to access a texture.
+ */
+class GrSamplerState {
+public:
+    enum class Filter : uint8_t { kNearest, kBilerp, kMipMap };
+    enum class WrapMode : uint8_t { kClamp, kRepeat, kMirrorRepeat };
+
+    static constexpr GrSamplerState ClampNearest() { return GrSamplerState(); }
+    static constexpr GrSamplerState ClampBilerp() {
+        return GrSamplerState(WrapMode::kClamp, Filter::kBilerp);
+    }
+
+    constexpr GrSamplerState() : GrSamplerState(WrapMode::kClamp, Filter::kNearest) {}
+
+    constexpr GrSamplerState(WrapMode wrapXAndY, Filter filter)
+            : fWrapModes{wrapXAndY, wrapXAndY}, fFilter(filter) {}
+
+    constexpr GrSamplerState(const WrapMode wrapModes[2], Filter filter)
+            : fWrapModes{wrapModes[0], wrapModes[1]}, fFilter(filter) {}
+
+    constexpr GrSamplerState(const GrSamplerState&) = default;
+
+    GrSamplerState& operator=(const GrSamplerState& that) {
+        fWrapModes[0] = that.fWrapModes[0];
+        fWrapModes[1] = that.fWrapModes[1];
+        fFilter = that.fFilter;
+        return *this;
+    }
+
+    Filter filter() const { return fFilter; }
+
+    void setFilterMode(Filter filterMode) { fFilter = filterMode; }
+
+    void setWrapModeX(const WrapMode wrap) { fWrapModes[0] = wrap; }
+    void setWrapModeY(const WrapMode wrap) { fWrapModes[1] = wrap; }
+
+    WrapMode wrapModeX() const { return fWrapModes[0]; }
+    WrapMode wrapModeY() const { return fWrapModes[1]; }
+
+    bool isRepeated() const {
+        return WrapMode::kClamp != fWrapModes[0] || WrapMode::kClamp != fWrapModes[1];
+    }
+
+    bool operator==(const GrSamplerState& that) const {
+        return fWrapModes[0] == that.fWrapModes[0] && fWrapModes[1] == that.fWrapModes[1] &&
+               fFilter == that.fFilter;
+    }
+
+    bool operator!=(const GrSamplerState& that) const { return !(*this == that); }
+
+private:
+    WrapMode fWrapModes[2];
+    Filter fFilter;
+};
+
+#endif