text: /*
   * Copyright 2017 Google Inc.
   *
   * Use of this source code is governed by a BSD-style license that can be
   * found in the LICENSE file.
   */
  
  #include "Test.h"
  
  #include "SkColorData.h"
  
  #define ASSERT(expr) REPORTER_ASSERT(r, expr)
  
  DEF_TEST(Splay, r) {
      const SkPMColor color = 0xA1B2C3D4;
  
      uint32_t ag, rb;
      SkSplay(color, &ag, &rb);
      ASSERT(ag == 0x00A100C3);
      ASSERT(rb == 0x00B200D4);
      ASSERT(SkUnsplay(ag << 8, rb << 8) == color);
  
      const uint64_t agrb = SkSplay(color);
      ASSERT(agrb == 0x00A100C300B200D4ULL);
      ASSERT(SkUnsplay(agrb<<8) == color);
  }
  
  DEF_TEST(FourByteInterp, r) {
      const SkPMColor src = 0xAB998877, dst = 0x66334455;
      for (unsigned scale = 0; scale <= 256; scale++) {
          ASSERT(SkFourByteInterp256(src, dst, scale) == SkFastFourByteInterp256(src, dst, scale));
      }
  
      for (unsigned scale = 0; scale < 256; scale++) {
          // SkFourByteInterp and SkFastFourByteInterp convert from [0, 255] to [0, 256] differently.
          // In particular, slow may end up a little too high (weirdly, fast is more accurate).
          const SkPMColor slow = SkFourByteInterp(src, dst, scale);
          const SkPMColor fast = SkFastFourByteInterp(src, dst, scale);
  
          const int deltaA = SkGetPackedA32(slow) - SkGetPackedA32(fast);
          const int deltaR = SkGetPackedR32(slow) - SkGetPackedR32(fast);
          const int deltaG = SkGetPackedG32(slow) - SkGetPackedG32(fast);
          const int deltaB = SkGetPackedB32(slow) - SkGetPackedB32(fast);
  
          ASSERT(deltaA == 0 || deltaA == 1);
          ASSERT(deltaR == 0 || deltaR == 1);
          ASSERT(deltaG == 0 || deltaG == 1);
          ASSERT(deltaB == 0 || deltaB == 1);
      }
  }
  