inline SkPMFloat& SkPMFloat::operator=(const SkPMFloat& that) { fColors = that.fColors; return *this; } // For SkPMFloat(SkPMFColor), we widen our 8 bit components (fix8) to 8-bit components in 16 bits // (fix8_16), then widen those to 8-bit-in-32-bits (fix8_32), and finally convert those to floats. // get() and clamped() do the opposite, working from floats to 8-bit-in-32-bit, // to 8-bit-in-16-bit, back down to 8-bit components. // clamped() uses vqmovn to clamp while narrowing instead of just narrowing with vmovn. inline SkPMFloat::SkPMFloat(SkPMColor c) { SkPMColorAssert(c); uint8x8_t fix8 = (uint8x8_t)vdup_n_u32(c); uint16x8_t fix8_16 = vmovl_u8(fix8); uint32x4_t fix8_32 = vmovl_u16(vget_low_u16(fix8_16)); fColors = vcvtq_f32_u32(fix8_32); SkASSERT(this->isValid()); } inline SkPMColor SkPMFloat::get() const { SkASSERT(this->isValid()); float32x4_t add_half = vaddq_f32(fColors, vdupq_n_f32(0.5f)); uint32x4_t fix8_32 = vcvtq_u32_f32(add_half); // vcvtq_u32_f32 truncates, so round manually uint16x4_t fix8_16 = vmovn_u32(fix8_32); uint8x8_t fix8 = vmovn_u16(vcombine_u16(fix8_16, vdup_n_u16(0))); SkPMColor c = vget_lane_u32((uint32x2_t)fix8, 0); SkPMColorAssert(c); return c; } inline SkPMColor SkPMFloat::clamped() const { float32x4_t add_half = vaddq_f32(fColors, vdupq_n_f32(0.5f)); uint32x4_t fix8_32 = vcvtq_u32_f32(add_half); // vcvtq_u32_f32 truncates, so round manually uint16x4_t fix8_16 = vqmovn_u32(fix8_32); uint8x8_t fix8 = vqmovn_u16(vcombine_u16(fix8_16, vdup_n_u16(0))); SkPMColor c = vget_lane_u32((uint32x2_t)fix8, 0); SkPMColorAssert(c); return c; } // TODO: we should be able to beat these loops on all three methods. inline void SkPMFloat::From4PMColors(SkPMFloat floats[4], const SkPMColor colors[4]) { for (int i = 0; i < 4; i++) { floats[i] = FromPMColor(colors[i]); } } inline void SkPMFloat::To4PMColors(SkPMColor colors[4], const SkPMFloat floats[4]) { for (int i = 0; i < 4; i++) { colors[i] = floats[i].get(); } } inline void SkPMFloat::ClampTo4PMColors(SkPMColor colors[4], const SkPMFloat floats[4]) { for (int i = 0; i < 4; i++) { colors[i] = floats[i].clamped(); } }