Refactored SkColorSpace and added in a Lab PCS GM

src/core/SkColorSpace.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkColorSpace.h"
 #include "SkColorSpace_Base.h"
+#include "SkColorSpace_XYZ.h"
 #include "SkColorSpacePriv.h"
-#include "SkColorSpaceXform_Base.h"
 #include "SkOnce.h"
 #include "SkPoint3.h"
 
 bool SkColorSpacePrimaries::toXYZD50(SkMatrix44* toXYZ_D50) const {
     if (!is_zero_to_one(fRX) || !is_zero_to_one(fRY) ||
         !is_zero_to_one(fGX) || !is_zero_to_one(fGY) ||
         !is_zero_to_one(fBX) || !is_zero_to_one(fBY) ||
         !is_zero_to_one(fWX) || !is_zero_to_one(fWY))
     {
         return false;
@@ skipping 54 matching lines @@
 
     toXYZ.postConcat(DXToD50);
     toXYZ_D50->set3x3(toXYZ[0], toXYZ[3], toXYZ[6],
                       toXYZ[1], toXYZ[4], toXYZ[7],
                       toXYZ[2], toXYZ[5], toXYZ[8]);
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
-SkColorSpace_Base::SkColorSpace_Base(SkGammaNamed gammaNamed, const SkMatrix44& toXYZD50)
-    : fGammaNamed(gammaNamed)
-    , fGammas(nullptr)
-    , fProfileData(nullptr)
-    , fToXYZD50(toXYZD50)
-    , fFromXYZD50(SkMatrix44::kUninitialized_Constructor)
-{}
-
-SkColorSpace_Base::SkColorSpace_Base(sk_sp<SkColorLookUpTable> colorLUT, SkGammaNamed gammaNamed,
-                                     sk_sp<SkGammas> gammas, const SkMatrix44& toXYZD50,
-                                     sk_sp<SkData> profileData)
-    : fColorLUT(std::move(colorLUT))
-    , fGammaNamed(gammaNamed)
-    , fGammas(std::move(gammas))
-    , fProfileData(std::move(profileData))
-    , fToXYZD50(toXYZD50)
-    , fFromXYZD50(SkMatrix44::kUninitialized_Constructor)
+SkColorSpace_Base::SkColorSpace_Base(sk_sp<SkData> profileData)
+    : fProfileData(std::move(profileData))
 {}
 
 static constexpr float gSRGB_toXYZD50[] {
     0.4358f, 0.3853f, 0.1430f,    // Rx, Gx, Bx
     0.2224f, 0.7170f, 0.0606f,    // Ry, Gy, Gz
     0.0139f, 0.0971f, 0.7139f,    // Rz, Gz, Bz
 };
 
 static constexpr float gAdobeRGB_toXYZD50[] {
     0.6098f, 0.2052f, 0.1492f,    // Rx, Gx, Bx
@@ skipping 43 matching lines @@
     }
 
     if (kNonStandard_SkGammaNamed == gammaNamed) {
         sk_sp<SkGammas> gammas = sk_sp<SkGammas>(new SkGammas());
         gammas->fRedType = SkGammas::Type::kValue_Type;
         gammas->fGreenType = SkGammas::Type::kValue_Type;
         gammas->fBlueType = SkGammas::Type::kValue_Type;
         gammas->fRedData.fValue = values[0];
         gammas->fGreenData.fValue = values[1];
         gammas->fBlueData.fValue = values[2];
-        return sk_sp<SkColorSpace>(new SkColorSpace_Base(nullptr, kNonStandard_SkGammaNamed, gammas,
-                                                         toXYZD50, nullptr));
+        return sk_sp<SkColorSpace>(new SkColorSpace_XYZ(kNonStandard_SkGammaNamed,
+                                                        gammas, toXYZD50, nullptr));
     }
 
     return SkColorSpace_Base::NewRGB(gammaNamed, toXYZD50);
 }
 
 sk_sp<SkColorSpace> SkColorSpace_Base::NewRGB(SkGammaNamed gammaNamed, const SkMatrix44& toXYZD50) {
     switch (gammaNamed) {
         case kSRGB_SkGammaNamed:
             if (xyz_almost_equal(toXYZD50, gSRGB_toXYZD50)) {
                 return SkColorSpace::NewNamed(kSRGB_Named);
             }
             break;
         case k2Dot2Curve_SkGammaNamed:
             if (xyz_almost_equal(toXYZD50, gAdobeRGB_toXYZD50)) {
                 return SkColorSpace::NewNamed(kAdobeRGB_Named);
             }
             break;
         case kLinear_SkGammaNamed:
             if (xyz_almost_equal(toXYZD50, gSRGB_toXYZD50)) {
                 return SkColorSpace::NewNamed(kSRGBLinear_Named);
             }
             break;
         case kNonStandard_SkGammaNamed:
             // This is not allowed.
             return nullptr;
         default:
             break;
     }
 
-    return sk_sp<SkColorSpace>(new SkColorSpace_Base(gammaNamed, toXYZD50));
+    return sk_sp<SkColorSpace>(new SkColorSpace_XYZ(gammaNamed, toXYZD50));
 }
 
 sk_sp<SkColorSpace> SkColorSpace::NewRGB(RenderTargetGamma gamma, const SkMatrix44& toXYZD50) {
     switch (gamma) {
         case kLinear_RenderTargetGamma:
             return SkColorSpace_Base::NewRGB(kLinear_SkGammaNamed, toXYZD50);
         case kSRGB_RenderTargetGamma:
             return SkColorSpace_Base::NewRGB(kSRGB_SkGammaNamed, toXYZD50);
         default:
             return nullptr;
@@ skipping 20 matching lines @@
     *fn = coeffs;
     gammas->fRedType = SkGammas::Type::kParam_Type;
     gammas->fGreenType = SkGammas::Type::kParam_Type;
     gammas->fBlueType = SkGammas::Type::kParam_Type;
 
     SkGammas::Data data;
     data.fParamOffset = 0;
     gammas->fRedData = data;
     gammas->fGreenData = data;
     gammas->fBlueData = data;
-    return sk_sp<SkColorSpace>(new SkColorSpace_Base(nullptr, kNonStandard_SkGammaNamed,
-                                                     std::move(gammas), toXYZD50, nullptr));
+    return sk_sp<SkColorSpace>(new SkColorSpace_XYZ(kNonStandard_SkGammaNamed,
+                                                    std::move(gammas), toXYZD50, nullptr));
 }
 
 static SkColorSpace* gAdobeRGB;
 static SkColorSpace* gSRGB;
 static SkColorSpace* gSRGBLinear;
 
 sk_sp<SkColorSpace> SkColorSpace::NewNamed(Named named) {
     static SkOnce sRGBOnce;
     static SkOnce adobeRGBOnce;
     static SkOnce sRGBLinearOnce;
 
     switch (named) {
         case kSRGB_Named: {
             sRGBOnce([] {
                 SkMatrix44 srgbToxyzD50(SkMatrix44::kUninitialized_Constructor);
                 srgbToxyzD50.set3x3RowMajorf(gSRGB_toXYZD50);
 
                 // Force the mutable type mask to be computed.  This avoids races.
                 (void)srgbToxyzD50.getType();
-                gSRGB = new SkColorSpace_Base(kSRGB_SkGammaNamed, srgbToxyzD50);
+                gSRGB = new SkColorSpace_XYZ(kSRGB_SkGammaNamed, srgbToxyzD50);
             });
             return sk_ref_sp<SkColorSpace>(gSRGB);
         }
         case kAdobeRGB_Named: {
             adobeRGBOnce([] {
                 SkMatrix44 adobergbToxyzD50(SkMatrix44::kUninitialized_Constructor);
                 adobergbToxyzD50.set3x3RowMajorf(gAdobeRGB_toXYZD50);
 
                 // Force the mutable type mask to be computed.  This avoids races.
                 (void)adobergbToxyzD50.getType();
-                gAdobeRGB = new SkColorSpace_Base(k2Dot2Curve_SkGammaNamed, adobergbToxyzD50);
+                gAdobeRGB = new SkColorSpace_XYZ(k2Dot2Curve_SkGammaNamed, adobergbToxyzD50);
             });
             return sk_ref_sp<SkColorSpace>(gAdobeRGB);
         }
         case kSRGBLinear_Named: {
             sRGBLinearOnce([] {
                 SkMatrix44 srgbToxyzD50(SkMatrix44::kUninitialized_Constructor);
                 srgbToxyzD50.set3x3RowMajorf(gSRGB_toXYZD50);
 
                 // Force the mutable type mask to be computed.  This avoids races.
                 (void)srgbToxyzD50.getType();
-                gSRGBLinear = new SkColorSpace_Base(kLinear_SkGammaNamed, srgbToxyzD50);
+                gSRGBLinear = new SkColorSpace_XYZ(kLinear_SkGammaNamed, srgbToxyzD50);
             });
             return sk_ref_sp<SkColorSpace>(gSRGBLinear);
         }
         default:
             break;
     }
     return nullptr;
 }
 
-sk_sp<SkColorSpace> SkColorSpace_Base::makeLinearGamma() {
-    if (this->gammaIsLinear()) {
-        return sk_ref_sp(this);
-    }
-    return SkColorSpace_Base::NewRGB(kLinear_SkGammaNamed, as_CSB(this)->fToXYZD50);
-}
-
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 bool SkColorSpace::gammaCloseToSRGB() const {
-    return kSRGB_SkGammaNamed == as_CSB(this)->fGammaNamed ||
-           k2Dot2Curve_SkGammaNamed == as_CSB(this)->fGammaNamed;
+    return as_CSB(this)->onGammaCloseToSRGB();
 }
 
 bool SkColorSpace::gammaIsLinear() const {
-    return kLinear_SkGammaNamed == as_CSB(this)->fGammaNamed;
-}
-
-const SkMatrix44& SkColorSpace_Base::fromXYZD50() const {
-    fFromXYZOnce([this] {
-        if (!fToXYZD50.invert(&fFromXYZD50)) {
-            // If a client gives us a dst gamut with a transform that we can't invert, we will
-            // simply give them back a transform to sRGB gamut.
-            SkDEBUGFAIL("Non-invertible XYZ matrix, defaulting to sRGB");
-            SkMatrix44 srgbToxyzD50(SkMatrix44::kUninitialized_Constructor);
-            srgbToxyzD50.set3x3RowMajorf(gSRGB_toXYZD50);
-            srgbToxyzD50.invert(&fFromXYZD50);
-        }
-    });
-    return fFromXYZD50;
-}
-
-void SkColorSpace_Base::toDstGammaTables(const uint8_t* tables[3], sk_sp<SkData>* storage,
-                                         int numTables) const {
-    fToDstGammaOnce([this, numTables] {
-        const bool gammasAreMatching = numTables <= 1;
-        fDstStorage =
-                SkData::MakeUninitialized(numTables * SkColorSpaceXform_Base::kDstGammaTableSize);
-        SkColorSpaceXform_Base::BuildDstGammaTables(fToDstGammaTables,
-                                                    (uint8_t*) fDstStorage->writable_data(), this,
-                                                    gammasAreMatching);
-    });
-
-    *storage = fDstStorage;
-    tables[0] = fToDstGammaTables[0];
-    tables[1] = fToDstGammaTables[1];
-    tables[2] = fToDstGammaTables[2];
+    return as_CSB(this)->onGammaIsLinear();
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 enum Version {
     k0_Version, // Initial version, header + flags for matrix and profile
 };
 
 struct ColorSpaceHeader {
     /**
@@ skipping 48 matching lines @@
     uint8_t fVersion;    // Always zero
     uint8_t fNamed;      // Must be a SkColorSpace::Named
     uint8_t fGammaNamed; // Must be a SkGammaNamed
     uint8_t fFlags;      // Some combination of the flags listed above
 };
 
 size_t SkColorSpace::writeToMemory(void* memory) const {
     // Start by trying the serialization fast path.  If we haven't saved ICC profile data,
     // we must have a profile that we can serialize easily.
     if (!as_CSB(this)->fProfileData) {
+        // Profile data is mandatory for A2B0 color spaces.
+        SkASSERT(SkColorSpace_Base::Type::kXYZ == as_CSB(this)->type());
+        const SkColorSpace_XYZ* thisXYZ = static_cast<const SkColorSpace_XYZ*>(this);
         // If we have a named profile, only write the enum.
+        const SkGammaNamed gammaNamed = thisXYZ->gammaNamed();
         if (this == gSRGB) {
             if (memory) {
                 *((ColorSpaceHeader*) memory) =
-                        ColorSpaceHeader::Pack(k0_Version, kSRGB_Named,
-                                               as_CSB(this)->fGammaNamed, 0);
+                        ColorSpaceHeader::Pack(k0_Version, kSRGB_Named, gammaNamed, 0);
             }
             return sizeof(ColorSpaceHeader);
         } else if (this == gAdobeRGB) {
             if (memory) {
                 *((ColorSpaceHeader*) memory) =
-                        ColorSpaceHeader::Pack(k0_Version, kAdobeRGB_Named,
-                                               as_CSB(this)->fGammaNamed, 0);
+                        ColorSpaceHeader::Pack(k0_Version, kAdobeRGB_Named, gammaNamed, 0);
             }
             return sizeof(ColorSpaceHeader);
         } else if (this == gSRGBLinear) {
             if (memory) {
-                *((ColorSpaceHeader*)memory) =
-                        ColorSpaceHeader::Pack(k0_Version, kSRGBLinear_Named,
-                                               as_CSB(this)->fGammaNamed, 0);
+                *((ColorSpaceHeader*) memory) =
+                        ColorSpaceHeader::Pack(k0_Version, kSRGBLinear_Named, gammaNamed, 0);
             }
             return sizeof(ColorSpaceHeader);
         }
 
         // If we have a named gamma, write the enum and the matrix.
-        switch (as_CSB(this)->fGammaNamed) {
+        switch (gammaNamed) {
             case kSRGB_SkGammaNamed:
             case k2Dot2Curve_SkGammaNamed:
             case kLinear_SkGammaNamed: {
                 if (memory) {
                     *((ColorSpaceHeader*) memory) =
-                            ColorSpaceHeader::Pack(k0_Version, 0, as_CSB(this)->fGammaNamed,
+                            ColorSpaceHeader::Pack(k0_Version, 0, gammaNamed,
                                                    ColorSpaceHeader::kMatrix_Flag);
                     memory = SkTAddOffset<void>(memory, sizeof(ColorSpaceHeader));
-                    as_CSB(this)->fToXYZD50.as3x4RowMajorf((float*) memory);
+                    thisXYZ->toXYZD50()->as3x4RowMajorf((float*) memory);
                 }
                 return sizeof(ColorSpaceHeader) + 12 * sizeof(float);
             }
             default:
-                const SkGammas* gammas = as_CSB(this)->gammas();
+                const SkGammas* gammas = thisXYZ->gammas();
                 SkASSERT(gammas);
                 if (gammas->isValue(0) && gammas->isValue(1) && gammas->isValue(2)) {
                     if (memory) {
                         *((ColorSpaceHeader*) memory) =
-                                ColorSpaceHeader::Pack(k0_Version, 0, as_CSB(this)->fGammaNamed,
+                                ColorSpaceHeader::Pack(k0_Version, 0, thisXYZ->fGammaNamed,
                                                        ColorSpaceHeader::kFloatGamma_Flag);
                         memory = SkTAddOffset<void>(memory, sizeof(ColorSpaceHeader));
 
                         *(((float*) memory) + 0) = gammas->fRedData.fValue;
                         *(((float*) memory) + 1) = gammas->fGreenData.fValue;
                         *(((float*) memory) + 2) = gammas->fBlueData.fValue;
                         memory = SkTAddOffset<void>(memory, 3 * sizeof(float));
 
-                        as_CSB(this)->fToXYZD50.as3x4RowMajorf((float*) memory);
+                        thisXYZ->fToXYZD50.as3x4RowMajorf((float*) memory);
                     }
 
                     return sizeof(ColorSpaceHeader) + 15 * sizeof(float);
                 } else {
                     SkASSERT(gammas->isParametric(0));
                     SkASSERT(gammas->isParametric(1));
                     SkASSERT(gammas->isParametric(2));
                     SkASSERT(gammas->data(0) == gammas->data(1));
                     SkASSERT(gammas->data(0) == gammas->data(2));
 
                     if (memory) {
                         *((ColorSpaceHeader*) memory) =
-                                ColorSpaceHeader::Pack(k0_Version, 0, as_CSB(this)->fGammaNamed,
+                                ColorSpaceHeader::Pack(k0_Version, 0, thisXYZ->fGammaNamed,
                                                        ColorSpaceHeader::kTransferFn_Flag);
                         memory = SkTAddOffset<void>(memory, sizeof(ColorSpaceHeader));
 
                         *(((float*) memory) + 0) = gammas->params(0).fA;
                         *(((float*) memory) + 1) = gammas->params(0).fB;
                         *(((float*) memory) + 2) = gammas->params(0).fC;
                         *(((float*) memory) + 3) = gammas->params(0).fD;
                         *(((float*) memory) + 4) = gammas->params(0).fE;
                         *(((float*) memory) + 5) = gammas->params(0).fF;
                         *(((float*) memory) + 6) = gammas->params(0).fG;
                         memory = SkTAddOffset<void>(memory, 7 * sizeof(float));
 
-                        as_CSB(this)->fToXYZD50.as3x4RowMajorf((float*) memory);
+                        thisXYZ->fToXYZD50.as3x4RowMajorf((float*) memory);
                     }
 
                     return sizeof(ColorSpaceHeader) + 19 * sizeof(float);
                 }
         }
     }
 
     // Otherwise, serialize the ICC data.
     size_t profileSize = as_CSB(this)->fProfileData->size();
     if (SkAlign4(profileSize) != (uint32_t) SkAlign4(profileSize)) {
@@ skipping 121 matching lines @@
     SkData* dstData = as_CSB(dst)->fProfileData.get();
     if (srcData || dstData) {
         if (srcData && dstData) {
             return srcData->size() == dstData->size() &&
                    0 == memcmp(srcData->data(), dstData->data(), srcData->size());
         }
 
         return false;
     }
 
-    // It's important to check fProfileData before named gammas.  Some profiles may have named
-    // gammas, but also include other wacky features that cause us to save the data.
-    switch (as_CSB(src)->fGammaNamed) {
+    // profiles are mandatory for A2B0 color spaces
+    SkASSERT(as_CSB(src)->type() == SkColorSpace_Base::Type::kXYZ);
+    const SkColorSpace_XYZ* srcXYZ = static_cast<const SkColorSpace_XYZ*>(src);
+    const SkColorSpace_XYZ* dstXYZ = static_cast<const SkColorSpace_XYZ*>(dst);
+
+    switch (srcXYZ->gammaNamed()) {
         case kSRGB_SkGammaNamed:
         case k2Dot2Curve_SkGammaNamed:
         case kLinear_SkGammaNamed:
-            return (as_CSB(src)->fGammaNamed == as_CSB(dst)->fGammaNamed) &&
-                   (as_CSB(src)->fToXYZD50 == as_CSB(dst)->fToXYZD50);
+            return (srcXYZ->gammaNamed() == dstXYZ->gammaNamed()) &&
+                   (*srcXYZ->toXYZD50() == *dstXYZ->toXYZD50());
         default:
-            if (as_CSB(src)->fGammaNamed != as_CSB(dst)->fGammaNamed) {
+            if (srcXYZ->gammaNamed() != dstXYZ->gammaNamed()) {
                 return false;
             }
-
             // It is unlikely that we will reach this case.
-            sk_sp<SkData> srcData = src->serialize();
-            sk_sp<SkData> dstData = dst->serialize();
-            return srcData->size() == dstData->size() &&
-                   0 == memcmp(srcData->data(), dstData->data(), srcData->size());
+            sk_sp<SkData> serializedSrcData = src->serialize();
+            sk_sp<SkData> serializedDstData = dst->serialize();
+            return serializedSrcData->size() == serializedDstData->size() &&
+                   0 == memcmp(serializedSrcData->data(), serializedDstData->data(),
+                               serializedSrcData->size());
     }
 }