Prepare SkColorSpace to be a public API

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 "SkAtomics.h"
 #include "SkColorSpace.h"
+#include "SkColorSpacePriv.h"
 #include "SkOnce.h"
 
 static bool color_space_almost_equal(float a, float b) {
     return SkTAbs(a - b) < 0.01f;
 }
 
-void SkFloat3::dump() const {
-    SkDebugf("[%7.4f %7.4f %7.4f]\n", fVec[0], fVec[1], fVec[2]);
-}
-
 //////////////////////////////////////////////////////////////////////////////////////////////////
 
 static int32_t gUniqueColorSpaceID;
 
-SkColorSpace::SkColorSpace(SkGammas gammas, const SkMatrix44& toXYZD50, Named named)
-    : fGammas(std::move(gammas))
+SkColorSpace::SkColorSpace(sk_sp<SkGammas> gammas, const SkMatrix44& toXYZD50, Named named)
+    : fGammas(gammas)
     , fToXYZD50(toXYZD50)
     , fUniqueID(sk_atomic_inc(&gUniqueColorSpaceID))
     , fNamed(named)
 {}
 
-SkColorSpace::SkColorSpace(SkColorLookUpTable colorLUT, SkGammas gammas,
+SkColorSpace::SkColorSpace(SkColorLookUpTable* colorLUT, sk_sp<SkGammas> gammas,
                            const SkMatrix44& toXYZD50)
-    : fColorLUT(std::move(colorLUT))
-    , fGammas(std::move(gammas))
+    : fColorLUT(colorLUT)
+    , fGammas(gammas)
     , fToXYZD50(toXYZD50)
     , fUniqueID(sk_atomic_inc(&gUniqueColorSpaceID))
     , fNamed(kUnknown_Named)
 {}
 
 const float gSRGB_toXYZD50[] {
     0.4358f, 0.2224f, 0.0139f,    // * R
     0.3853f, 0.7170f, 0.0971f,    // * G
     0.1430f, 0.0606f, 0.7139f,    // * B
 };
@@ skipping 22 matching lines @@
            color_space_almost_equal(toXYZD50.getFloat(2, 2), standard[8]) &&
            color_space_almost_equal(toXYZD50.getFloat(0, 3), 0.0f) &&
            color_space_almost_equal(toXYZD50.getFloat(1, 3), 0.0f) &&
            color_space_almost_equal(toXYZD50.getFloat(2, 3), 0.0f) &&
            color_space_almost_equal(toXYZD50.getFloat(3, 0), 0.0f) &&
            color_space_almost_equal(toXYZD50.getFloat(3, 1), 0.0f) &&
            color_space_almost_equal(toXYZD50.getFloat(3, 2), 0.0f) &&
            color_space_almost_equal(toXYZD50.getFloat(3, 3), 1.0f);
 }
 
-sk_sp<SkColorSpace> SkColorSpace::NewRGB(SkGammas gammas, const SkMatrix44& toXYZD50) {
+static SkOnce gStandardGammasOnce;
+static SkGammas* gStandardGammas;
+
+sk_sp<SkColorSpace> SkColorSpace::NewRGB(float gammaVals[3], const SkMatrix44& toXYZD50) {
+    sk_sp<SkGammas> gammas = nullptr;
+
     // Check if we really have sRGB or Adobe RGB
-    if (color_space_almost_equal(2.2f, gammas.fRed.fValue) &&
-        color_space_almost_equal(2.2f, gammas.fGreen.fValue) &&
-        color_space_almost_equal(2.2f, gammas.fBlue.fValue))
+    if (color_space_almost_equal(2.2f, gammaVals[0]) &&
+        color_space_almost_equal(2.2f, gammaVals[1]) &&
+        color_space_almost_equal(2.2f, gammaVals[2]))
     {
+        gStandardGammasOnce([] {
+            gStandardGammas = new SkGammas(2.2f, 2.2f, 2.2f);
+        });
+        gammas = sk_ref_sp(gStandardGammas);
+
         if (xyz_almost_equal(toXYZD50, gSRGB_toXYZD50)) {
             return SkColorSpace::NewNamed(kSRGB_Named);
         } else if (xyz_almost_equal(toXYZD50, gAdobeRGB_toXYZD50)) {
             return SkColorSpace::NewNamed(kAdobeRGB_Named);
         }
     }
 
-    return sk_sp<SkColorSpace>(new SkColorSpace(std::move(gammas), toXYZD50, kUnknown_Named));
+    if (!gammas) {
+        gammas = sk_ref_sp(new SkGammas(gammaVals[0], gammaVals[1], gammaVals[2]));
+    }
+    return sk_sp<SkColorSpace>(new SkColorSpace(gammas, toXYZD50, kUnknown_Named));
 }
 
 sk_sp<SkColorSpace> SkColorSpace::NewNamed(Named named) {
     static SkOnce sRGBOnce;
     static SkColorSpace* sRGB;
     static SkOnce adobeRGBOnce;
     static SkColorSpace* adobeRGB;
 
     switch (named) {
         case kSRGB_Named: {
+            gStandardGammasOnce([] {
+                gStandardGammas = new SkGammas(2.2f, 2.2f, 2.2f);
+            });
+
             sRGBOnce([] {
                 SkMatrix44 srgbToxyzD50(SkMatrix44::kUninitialized_Constructor);
                 srgbToxyzD50.set3x3ColMajorf(gSRGB_toXYZD50);
-                sRGB = new SkColorSpace(SkGammas(2.2f, 2.2f, 2.2f), srgbToxyzD50, kSRGB_Named);
+                sRGB = new SkColorSpace(sk_ref_sp(gStandardGammas), srgbToxyzD50, kSRGB_Named);
             });
             return sk_ref_sp(sRGB);
         }
         case kAdobeRGB_Named: {
+            gStandardGammasOnce([] {
+                gStandardGammas = new SkGammas(2.2f, 2.2f, 2.2f);
+            });
+
             adobeRGBOnce([] {
                 SkMatrix44 adobergbToxyzD50(SkMatrix44::kUninitialized_Constructor);
                 adobergbToxyzD50.set3x3ColMajorf(gAdobeRGB_toXYZD50);
-                adobeRGB = new SkColorSpace(SkGammas(2.2f, 2.2f, 2.2f), adobergbToxyzD50,
+                adobeRGB = new SkColorSpace(sk_ref_sp(gStandardGammas), adobergbToxyzD50,
                                             kAdobeRGB_Named);
             });
             return sk_ref_sp(adobeRGB);
         }
         default:
             break;
     }
     return nullptr;
 }
 
@@ skipping 406 matching lines @@
     array[10] = SkFixedToFloat(read_big_endian_int(src + 32));
     array[11] = 0;
     array[12] = SkFixedToFloat(read_big_endian_int(src + 36));  // translate R
     array[13] = SkFixedToFloat(read_big_endian_int(src + 40));  // translate G
     array[14] = SkFixedToFloat(read_big_endian_int(src + 44));
     array[15] = 1;
     toXYZ->setColMajorf(array);
     return true;
 }
 
-bool SkColorSpace::LoadA2B0(SkColorLookUpTable* colorLUT, SkGammas* gammas, SkMatrix44* toXYZ,
+bool SkColorSpace::LoadA2B0(SkColorLookUpTable* colorLUT, sk_sp<SkGammas> gammas, SkMatrix44* toXYZ,
                             const uint8_t* src, size_t len) {
     if (len < 32) {
         SkColorSpacePrintf("A to B tag is too small (%d bytes).", len);
         return false;
     }
 
     uint32_t type = read_big_endian_uint(src);
     if (kTAG_AtoBType != type) {
         // FIXME (msarett): Need to support lut8Type and lut16Type.
         SkColorSpacePrintf("Unsupported A to B tag type.\n");
@@ skipping 105 matching lines @@
                 float toXYZ[9];
                 if (!load_xyz(&toXYZ[0], r->addr((const uint8_t*) base), r->fLength) ||
                     !load_xyz(&toXYZ[3], g->addr((const uint8_t*) base), g->fLength) ||
                     !load_xyz(&toXYZ[6], b->addr((const uint8_t*) base), b->fLength))
                 {
                     return_null("Need valid rgb tags for XYZ space");
                 }
 
                 // It is not uncommon to see missing or empty gamma tags.  This indicates
                 // that we should use unit gamma.
-                SkGammas gammas;
+                sk_sp<SkGammas> gammas(new SkGammas());
                 r = ICCTag::Find(tags.get(), tagCount, kTAG_rTRC);
                 g = ICCTag::Find(tags.get(), tagCount, kTAG_gTRC);
                 b = ICCTag::Find(tags.get(), tagCount, kTAG_bTRC);
-                if (!r || !SkColorSpace::LoadGammas(&gammas.fRed, 1,
+                if (!r || !SkColorSpace::LoadGammas(&gammas->fRed, 1,
                                                     r->addr((const uint8_t*) base), r->fLength)) {
                     SkColorSpacePrintf("Failed to read R gamma tag.\n");
                 }
-                if (!g || !SkColorSpace::LoadGammas(&gammas.fGreen, 1,
+                if (!g || !SkColorSpace::LoadGammas(&gammas->fGreen, 1,
                                                     g->addr((const uint8_t*) base), g->fLength)) {
                     SkColorSpacePrintf("Failed to read G gamma tag.\n");
                 }
-                if (!b || !SkColorSpace::LoadGammas(&gammas.fBlue, 1,
+                if (!b || !SkColorSpace::LoadGammas(&gammas->fBlue, 1,
                                                     b->addr((const uint8_t*) base), b->fLength)) {
                     SkColorSpacePrintf("Failed to read B gamma tag.\n");
                 }
 
                 SkMatrix44 mat(SkMatrix44::kUninitialized_Constructor);
                 mat.set3x3ColMajorf(toXYZ);
-                return SkColorSpace::NewRGB(std::move(gammas), mat);
+                if (gammas->isValues()) {
+                    // When we have values, take advantage of the NewFromRGB initializer.
+                    // This allows us to check for canonical sRGB and Adobe RGB.
+                    float gammaVals[3];
+                    gammaVals[0] = gammas->fRed.fValue;
+                    gammaVals[1] = gammas->fGreen.fValue;
+                    gammaVals[2] = gammas->fBlue.fValue;
+                    return SkColorSpace::NewRGB(gammaVals, mat);
+                } else {
+                    return sk_sp<SkColorSpace>(new SkColorSpace(gammas, mat, kUnknown_Named));
+                }
             }
 
             // Recognize color profile specified by A2B0 tag.
             const ICCTag* a2b0 = ICCTag::Find(tags.get(), tagCount, kTAG_A2B0);
             if (a2b0) {
-                SkColorLookUpTable colorLUT;
-                SkGammas gammas;
+                SkAutoTDelete<SkColorLookUpTable> colorLUT(new SkColorLookUpTable());
+                sk_sp<SkGammas> gammas(new SkGammas());
                 SkMatrix44 toXYZ(SkMatrix44::kUninitialized_Constructor);
-                if (!SkColorSpace::LoadA2B0(&colorLUT, &gammas, &toXYZ,
+                if (!SkColorSpace::LoadA2B0(colorLUT, gammas, &toXYZ,
                                             a2b0->addr((const uint8_t*) base), a2b0->fLength)) {
                     return_null("Failed to parse A2B0 tag");
                 }
 
-                // If there is no colorLUT, use NewRGB.  This allows us to check if the
-                // profile is sRGB.
-                if (!colorLUT.fTable) {
-                    return SkColorSpace::NewRGB(std::move(gammas), toXYZ);
+                if (colorLUT->fTable) {
+                    return sk_sp<SkColorSpace>(new SkColorSpace(colorLUT.release(), gammas, toXYZ));
+                } else if (gammas->isValues()) {
+                    // When we have values, take advantage of the NewFromRGB initializer.
+                    // This allows us to check for canonical sRGB and Adobe RGB.
+                    float gammaVals[3];
+                    gammaVals[0] = gammas->fRed.fValue;
+                    gammaVals[1] = gammas->fGreen.fValue;
+                    gammaVals[2] = gammas->fBlue.fValue;
+                    return SkColorSpace::NewRGB(gammaVals, toXYZ);
+                } else {
+                    return sk_sp<SkColorSpace>(new SkColorSpace(gammas, toXYZ, kUnknown_Named));
                 }
-
-                return sk_sp<SkColorSpace>(new SkColorSpace(std::move(colorLUT), std::move(gammas),
-                                                            toXYZ));
             }
 
         }
         default:
             break;
     }
 
     return_null("ICC profile contains unsupported colorspace");
 }