1 files changed, 165 insertions, 0 deletions
diff --git a/src/utils/SkColorMatrix.cpp b/src/utils/SkColorMatrix.cpp
new file mode 100644
index 0000000..0a20990
--- /dev/null
+++ b/src/utils/SkColorMatrix.cpp
@@ -0,0 +1,165 @@
+#include "SkColorMatrix.h"
+
+#define kRScale     0
+#define kGScale     6
+#define kBScale     12
+#define kAScale     18
+
+void SkColorMatrix::setIdentity()
+{
+    memset(fMat, 0, sizeof(fMat));
+    fMat[kRScale] = fMat[kGScale] = fMat[kBScale] = fMat[kAScale] = SK_Scalar1;
+}
+
+void SkColorMatrix::setScale(SkScalar rScale, SkScalar gScale, SkScalar bScale,
+                             SkScalar aScale)
+{
+    memset(fMat, 0, sizeof(fMat));
+    fMat[kRScale] = rScale;
+    fMat[kGScale] = gScale;
+    fMat[kBScale] = bScale;
+    fMat[kAScale] = aScale;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkColorMatrix::setRotate(Axis axis, SkScalar degrees)
+{
+    SkScalar S, C;
+
+    S = SkScalarSinCos(SkDegreesToRadians(degrees), &C);
+
+    this->setSinCos(axis, S, C);
+}
+
+void SkColorMatrix::setSinCos(Axis axis, SkScalar sine, SkScalar cosine)
+{
+    SkASSERT((unsigned)axis < 3);
+
+    static const uint8_t gRotateIndex[] = {
+        6, 7, 11, 12,
+        0, 2, 15, 17,
+        0, 1,  5,  6,
+    };
+    const uint8_t* index = gRotateIndex + axis * 4;
+    
+    this->setIdentity();
+    fMat[index[0]] = cosine;
+    fMat[index[1]] = sine;
+    fMat[index[2]] = -sine;
+    fMat[index[3]] = cosine;
+}
+
+void SkColorMatrix::preRotate(Axis axis, SkScalar degrees)
+{
+    SkColorMatrix tmp;
+    tmp.setRotate(axis, degrees);
+    this->preConcat(tmp);
+}
+
+void SkColorMatrix::postRotate(Axis axis, SkScalar degrees)
+{
+    SkColorMatrix tmp;
+    tmp.setRotate(axis, degrees);
+    this->postConcat(tmp);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkColorMatrix::setConcat(const SkColorMatrix& matA,
+                              const SkColorMatrix& matB)
+{
+    SkScalar    tmp[20];
+    SkScalar*   result = fMat;
+
+    if (&matA == this || &matB == this)
+        result = tmp;
+    
+    const SkScalar* a = matA.fMat;
+    const SkScalar* b = matB.fMat;
+
+    int index = 0;
+    for (int j = 0; j < 20; j += 5)
+    {
+        for (int i = 0; i < 4; i++)
+        {
+            result[index++] =   SkScalarMul(a[j + 0], b[i + 0]) + 
+                                SkScalarMul(a[j + 1], b[i + 5]) +
+                                SkScalarMul(a[j + 2], b[i + 10]) +
+                                SkScalarMul(a[j + 3], b[i + 15]);
+        }
+        result[index++] =   SkScalarMul(a[j + 0], b[4]) +
+                            SkScalarMul(a[j + 1], b[9]) +
+                            SkScalarMul(a[j + 2], b[14]) +
+                            SkScalarMul(a[j + 3], b[19]) +
+                            a[j + 4];
+    }
+    
+    if (fMat != result)
+        memcpy(fMat, result, sizeof(fMat));
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+static void setrow(SkScalar row[], SkScalar r, SkScalar g, SkScalar b)
+{
+    row[0] = r;
+    row[1] = g;
+    row[2] = b;
+}
+
+static const SkScalar kHueR = SkFloatToScalar(0.213f);
+static const SkScalar kHueG = SkFloatToScalar(0.715f);
+static const SkScalar kHueB = SkFloatToScalar(0.072f);
+
+void SkColorMatrix::setSaturation(SkScalar sat)
+{
+    memset(fMat, 0, sizeof(fMat));
+
+    const SkScalar R = SkScalarMul(kHueR, SK_Scalar1 - sat);
+    const SkScalar G = SkScalarMul(kHueG, SK_Scalar1 - sat);
+    const SkScalar B = SkScalarMul(kHueB, SK_Scalar1 - sat);
+
+    setrow(fMat +  0, R + sat, G, B);
+    setrow(fMat +  5, R, G + sat, B);
+    setrow(fMat + 10, R, G, B + sat);
+    fMat[18] = SK_Scalar1;
+}
+
+static const SkScalar kR2Y = SkFloatToScalar(0.299f);
+static const SkScalar kG2Y = SkFloatToScalar(0.587f);
+static const SkScalar kB2Y = SkFloatToScalar(0.114f);
+
+static const SkScalar kR2U = SkFloatToScalar(-0.16874f);
+static const SkScalar kG2U = SkFloatToScalar(-0.33126f);
+static const SkScalar kB2U = SkFloatToScalar(0.5f);
+
+static const SkScalar kR2V = SkFloatToScalar(0.5f);
+static const SkScalar kG2V = SkFloatToScalar(-0.41869f);
+static const SkScalar kB2V = SkFloatToScalar(-0.08131f);
+
+void SkColorMatrix::setRGB2YUV()
+{
+    memset(fMat, 0, sizeof(fMat));
+    
+    setrow(fMat +  0, kR2Y, kG2Y, kB2Y);
+    setrow(fMat +  5, kR2U, kG2U, kB2U);
+    setrow(fMat + 10, kR2V, kG2V, kB2V);
+    fMat[18] = SK_Scalar1;
+}
+
+static const SkScalar kV2R = SkFloatToScalar(1.402f);
+static const SkScalar kU2G = SkFloatToScalar(-0.34414f);
+static const SkScalar kV2G = SkFloatToScalar(-0.71414f);
+static const SkScalar kU2B = SkFloatToScalar(1.772f);
+
+void SkColorMatrix::setYUV2RGB()
+{
+    memset(fMat, 0, sizeof(fMat));
+    
+    setrow(fMat +  0, SK_Scalar1, 0, kV2R);
+    setrow(fMat +  5, SK_Scalar1, kU2G, kV2G);
+    setrow(fMat + 10, SK_Scalar1, kU2B, 0);
+    fMat[18] = SK_Scalar1;
+}
+