1 files changed, 119 insertions, 0 deletions
diff --git a/src/core/SkColorSpaceXform_skcms.cpp b/src/core/SkColorSpaceXform_skcms.cpp
new file mode 100644
index 0000000000..34afaaa7c5
--- /dev/null
+++ b/src/core/SkColorSpaceXform_skcms.cpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkColorSpaceXform.h"
+#include "SkData.h"
+#include "SkMakeUnique.h"
+#include "skcms.h"
+
+class SkColorSpaceXform_skcms : public SkColorSpaceXform {
+public:
+    SkColorSpaceXform_skcms(const skcms_ICCProfile& srcProfile,
+                            const skcms_ICCProfile& dstProfile,
+                            skcms_AlphaFormat premulFormat)
+        : fSrcProfile(srcProfile)
+        , fDstProfile(dstProfile)
+        , fPremulFormat(premulFormat)
+    {}
+
+    bool apply(ColorFormat, void*, ColorFormat, const void*, int, SkAlphaType) const override;
+
+private:
+    skcms_ICCProfile  fSrcProfile;
+    skcms_ICCProfile  fDstProfile;
+    skcms_AlphaFormat fPremulFormat;
+};
+
+static skcms_PixelFormat get_skcms_format(SkColorSpaceXform::ColorFormat fmt) {
+    switch (fmt) {
+        case SkColorSpaceXform::kRGBA_8888_ColorFormat:
+            return skcms_PixelFormat_RGBA_8888;
+        case SkColorSpaceXform::kBGRA_8888_ColorFormat:
+            return skcms_PixelFormat_BGRA_8888;
+        case SkColorSpaceXform::kRGB_U16_BE_ColorFormat:
+            return skcms_PixelFormat_RGB_161616;
+        case SkColorSpaceXform::kRGBA_U16_BE_ColorFormat:
+            return skcms_PixelFormat_RGBA_16161616;
+        case SkColorSpaceXform::kRGBA_F16_ColorFormat:
+            return skcms_PixelFormat_RGBA_hhhh;
+        case SkColorSpaceXform::kRGBA_F32_ColorFormat:
+            return skcms_PixelFormat_RGBA_ffff;
+        case SkColorSpaceXform::kBGR_565_ColorFormat:
+            return skcms_PixelFormat_BGR_565;
+        default:
+            SkDEBUGFAIL("Invalid ColorFormat");
+            return skcms_PixelFormat_RGBA_8888;
+    }
+}
+
+bool SkColorSpaceXform_skcms::apply(ColorFormat dstFormat, void* dst,
+                                    ColorFormat srcFormat, const void* src,
+                                    int count, SkAlphaType alphaType) const {
+    skcms_AlphaFormat srcAlpha = skcms_AlphaFormat_Unpremul;
+    skcms_AlphaFormat dstAlpha = kPremul_SkAlphaType == alphaType ? fPremulFormat
+                                                                  : skcms_AlphaFormat_Unpremul;
+
+    return skcms_Transform(src, get_skcms_format(srcFormat), srcAlpha, &fSrcProfile,
+                           dst, get_skcms_format(dstFormat), dstAlpha, &fDstProfile, count);
+}
+
+static bool cs_to_profile(const SkColorSpace* cs, skcms_ICCProfile* profile) {
+    if (cs->profileData()) {
+        bool result = skcms_Parse(cs->profileData()->data(), cs->profileData()->size(), profile);
+        // We shouldn't encounter color spaces that were constructed from invalid profiles!
+        SkASSERT(result);
+        return result;
+    }
+
+    SkMatrix44 toXYZ;
+    SkColorSpaceTransferFn tf;
+    if (cs->toXYZD50(&toXYZ) && cs->isNumericalTransferFn(&tf)) {
+        memset(profile, 0, sizeof(*profile));
+
+        profile->has_trc = true;
+        profile->trc[0].parametric.g = tf.fG;
+        profile->trc[0].parametric.a = tf.fA;
+        profile->trc[0].parametric.b = tf.fB;
+        profile->trc[0].parametric.c = tf.fC;
+        profile->trc[0].parametric.d = tf.fD;
+        profile->trc[0].parametric.e = tf.fE;
+        profile->trc[0].parametric.f = tf.fF;
+        profile->trc[1].parametric = profile->trc[0].parametric;
+        profile->trc[2].parametric = profile->trc[0].parametric;
+
+        profile->has_toXYZD50 = true;
+        for (int r = 0; r < 3; ++r) {
+            for (int c = 0; c < 3; ++c) {
+                profile->toXYZD50.vals[r][c] = toXYZ.get(r, c);
+            }
+        }
+
+        return true;
+    }
+
+    // It should be impossible to make a color space that gets here with our available factories.
+    // All ICC-based profiles have profileData. All remaining factories produce XYZ spaces with
+    // a single (numerical) transfer function.
+    SkDEBUGFAIL("How did we get here?");
+    return false;
+}
+
+std::unique_ptr<SkColorSpaceXform> MakeSkcmsXform(SkColorSpace* src, SkColorSpace* dst,
+                                                  SkTransferFunctionBehavior premulBehavior) {
+    // Construct skcms_ICCProfiles from each color space. For now, support A2B and XYZ.
+    // Eventually, only need to support XYZ. Map premulBehavior to one of the two premul formats
+    // in skcms.
+    skcms_ICCProfile srcProfile, dstProfile;
+
+    if (!cs_to_profile(src, &srcProfile) || !cs_to_profile(dst, &dstProfile)) {
+        return nullptr;
+    }
+
+    skcms_AlphaFormat premulFormat = SkTransferFunctionBehavior::kRespect == premulBehavior
+            ? skcms_AlphaFormat_PremulLinear : skcms_AlphaFormat_PremulAsEncoded;
+    return skstd::make_unique<SkColorSpaceXform_skcms>(srcProfile, dstProfile, premulFormat);
+}