| /* |
| * Copyright 2016 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SkPM4fPriv_DEFINED |
| #define SkPM4fPriv_DEFINED |
| |
| #include "SkColorPriv.h" |
| #include "SkPM4f.h" |
| |
| extern bool gTreatSkColorAsSRGB; |
| |
| static inline float get_alpha(const Sk4f& f4) { |
| return f4[SkPM4f::A]; |
| } |
| |
| static inline Sk4f set_alpha(const Sk4f& f4, float alpha) { |
| static_assert(3 == SkPM4f::A, ""); |
| return Sk4f(f4[0], f4[1], f4[2], alpha); |
| } |
| |
| static inline uint32_t to_4b(const Sk4f& f4) { |
| uint32_t b4; |
| SkNx_cast<uint8_t>(f4).store((uint8_t*)&b4); |
| return b4; |
| } |
| |
| static inline Sk4f to_4f(uint32_t b4) { |
| return SkNx_cast<float>(Sk4b::Load((const uint8_t*)&b4)); |
| } |
| |
| static inline Sk4f to_4f_rgba(uint32_t b4) { |
| return swizzle_rb_if_bgra(to_4f(b4)); |
| } |
| |
| static inline Sk4f srgb_to_linear(const Sk4f& s4) { |
| return set_alpha(s4 * s4, get_alpha(s4)); |
| } |
| |
| static inline Sk4f linear_to_srgb(const Sk4f& l4) { |
| return set_alpha(l4.rsqrt().invert(), get_alpha(l4)); |
| } |
| |
| static inline float srgb_to_linear(float x) { |
| return x * x; |
| } |
| |
| static inline float linear_to_srgb(float x) { |
| return sqrtf(x); |
| } |
| |
| static void assert_unit(float x) { |
| SkASSERT(x >= 0 && x <= 1); |
| } |
| |
| static inline float exact_srgb_to_linear(float x) { |
| assert_unit(x); |
| float linear; |
| if (x <= 0.04045) { |
| linear = x / 12.92f; |
| } else { |
| linear = powf((x + 0.055f) / 1.055f, 2.4f); |
| } |
| assert_unit(linear); |
| return linear; |
| } |
| |
| static inline float exact_linear_to_srgb(float x) { |
| assert_unit(x); |
| float srgb; |
| if (x <= 0.0031308f) { |
| srgb = x * 12.92f; |
| } else { |
| srgb = 1.055f * powf(x, 0.41666667f) - 0.055f; |
| } |
| assert_unit(srgb); |
| return srgb; |
| } |
| |
| static inline Sk4f exact_srgb_to_linear(const Sk4f& x) { |
| Sk4f linear(exact_srgb_to_linear(x[0]), |
| exact_srgb_to_linear(x[1]), |
| exact_srgb_to_linear(x[2]), 1); |
| return set_alpha(linear, get_alpha(x)); |
| } |
| |
| static inline Sk4f exact_linear_to_srgb(const Sk4f& x) { |
| Sk4f srgb(exact_linear_to_srgb(x[0]), |
| exact_linear_to_srgb(x[1]), |
| exact_linear_to_srgb(x[2]), 1); |
| return set_alpha(srgb, get_alpha(x)); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| static inline Sk4f Sk4f_fromL32(uint32_t src) { |
| return to_4f(src) * Sk4f(1.0f/255); |
| } |
| |
| static inline Sk4f Sk4f_fromS32(uint32_t src) { |
| return srgb_to_linear(to_4f(src) * Sk4f(1.0f/255)); |
| } |
| |
| // Color handling: |
| // SkColor has an ordering of (b, g, r, a) if cast to an Sk4f, so the code swizzles r and b to |
| // produce the needed (r, g, b, a) ordering. |
| static inline Sk4f Sk4f_from_SkColor(SkColor color) { |
| return swizzle_rb(gTreatSkColorAsSRGB ? Sk4f_fromS32(color) : Sk4f_fromL32(color)); |
| } |
| |
| static inline uint32_t Sk4f_toL32(const Sk4f& x4) { |
| return to_4b(x4 * Sk4f(255) + Sk4f(0.5f)); |
| } |
| |
| static inline uint32_t Sk4f_toS32(const Sk4f& x4) { |
| return to_4b(linear_to_srgb(x4) * Sk4f(255) + Sk4f(0.5f)); |
| } |
| |
| static inline Sk4f exact_Sk4f_fromS32(uint32_t src) { |
| return exact_srgb_to_linear(to_4f(src) * Sk4f(1.0f/255)); |
| } |
| static inline uint32_t exact_Sk4f_toS32(const Sk4f& x4) { |
| return to_4b(exact_linear_to_srgb(x4) * Sk4f(255) + Sk4f(0.5f)); |
| } |
| |
| #endif |