Index: src/gpu/GrSwizzle.h |
diff --git a/src/gpu/GrSwizzle.h b/src/gpu/GrSwizzle.h |
index 87ea9534b9e021bfc6d5b1d0e942b1c5168307fd..48748803ddb2d3daceea66233d7a0d238ff61b38 100644 |
--- a/src/gpu/GrSwizzle.h |
+++ b/src/gpu/GrSwizzle.h |
@@ -9,6 +9,7 @@ |
#define GrSwizzle_DEFINED |
#include "GrTypes.h" |
+#include "GrColor.h" |
/** Represents a rgba swizzle. It can be converted either into a string or a eight bit int. |
Currently there is no way to specify an arbitrary swizzle, just some static swizzles and an |
@@ -17,11 +18,23 @@ class GrSwizzle { |
public: |
GrSwizzle() { *this = RGBA(); } |
+ GrSwizzle(const GrSwizzle& that) { *this = that; } |
+ |
GrSwizzle& operator=(const GrSwizzle& that) { |
memcpy(this, &that, sizeof(GrSwizzle)); |
return *this; |
} |
+ /** Recreates a GrSwizzle from the output of asKey() */ |
+ void setFromKey(uint8_t key) { |
+ fKey = key; |
+ for (int i = 0; i < 4; ++i) { |
+ fSwiz[i] = IdxToChar(key & 3); |
+ key >>= 2; |
+ } |
+ SkASSERT(fSwiz[4] == 0); |
+ } |
+ |
bool operator==(const GrSwizzle& that) const { return this->asUInt() == that.asUInt(); } |
bool operator!=(const GrSwizzle& that) const { return !(*this == that); } |
@@ -32,6 +45,25 @@ public: |
/** 4 char null terminated string consisting only of chars 'r', 'g', 'b', 'a'. */ |
const char* c_str() const { return fSwiz; } |
+ /** Applies this swizzle to the input color and returns the swizzled color. */ |
+ GrColor applyTo(GrColor color) const { |
+ int idx; |
+ uint32_t key = fKey; |
+ // Index of the input color that should be mapped to output r. |
+ idx = (key & 3); |
+ uint32_t outR = (color >> idx * 8) & 0xFF; |
+ key >>= 2; |
+ idx = (key & 3); |
+ uint32_t outG = (color >> idx * 8) & 0xFF; |
+ key >>= 2; |
+ idx = (key & 3); |
+ uint32_t outB = (color >> idx * 8) & 0xFF; |
+ key >>= 2; |
+ idx = (key & 3); |
+ uint32_t outA = (color >> idx * 8) & 0xFF; |
+ return GrColorPackRGBA(outR, outG, outB, outA); |
+ } |
+ |
static const GrSwizzle& RGBA() { |
static GrSwizzle gRGBA("rgba"); |
return gRGBA; |
@@ -59,19 +91,31 @@ private: |
static int CharToIdx(char c) { |
switch (c) { |
case 'r': |
- return 0; |
+ return (GrColor_SHIFT_R / 8); |
case 'g': |
- return 1; |
+ return (GrColor_SHIFT_G / 8); |
case 'b': |
- return 2; |
+ return (GrColor_SHIFT_B / 8); |
case 'a': |
- return 3; |
+ return (GrColor_SHIFT_A / 8); |
default: |
SkFAIL("Invalid swizzle char"); |
return 0; |
} |
} |
+ static /* constexpr */ char IToC(int idx) { |
+ return (8*idx) == GrColor_SHIFT_R ? 'r' : |
+ (8*idx) == GrColor_SHIFT_G ? 'g' : |
+ (8*idx) == GrColor_SHIFT_B ? 'b' : 'a'; |
+ } |
+ |
+ static char IdxToChar(int c) { |
+ // Hopefully this array gets computed at compile time. |
+ static const char gStr[4] = { IToC(0), IToC(1), IToC(2), IToC(3) }; |
+ return gStr[c]; |
+ } |
+ |
explicit GrSwizzle(const char* str) { |
SkASSERT(strlen(str) == 4); |
fSwiz[0] = str[0]; |