move into utils
git-svn-id: http://skia.googlecode.com/svn/trunk@1563 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/utils/SkMatrix44.cpp b/src/utils/SkMatrix44.cpp
new file mode 100644
index 0000000..803747f
--- /dev/null
+++ b/src/utils/SkMatrix44.cpp
@@ -0,0 +1,340 @@
+/*
+ Copyright 2011 Google Inc.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+
+#include "SkMatrix44.h"
+
+SkMatrix44::SkMatrix44() {
+ this->setIdentity();
+}
+
+SkMatrix44::SkMatrix44(const SkMatrix44& src) {
+ memcpy(this, &src, sizeof(src));
+}
+
+SkMatrix44::SkMatrix44(const SkMatrix44& a, const SkMatrix44& b) {
+ this->setConcat(a, b);
+}
+
+SkMScalar SkMatrix44::get(int row, int col) const {
+ SkASSERT(row <= 3 && row >= 0);
+ SkASSERT(col <= 3 && col >= 0);
+ return fMat[col][row];
+}
+
+void SkMatrix44::set(int row, int col, const SkMScalar& value) {
+ SkASSERT(row <= 3 && row >= 0);
+ SkASSERT(col <= 3 && col >= 0);
+ fMat[col][row] = value;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+static const SkMatrix44 gIdentity44;
+
+bool SkMatrix44::isIdentity() const {
+ return *this == gIdentity44;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::setIdentity() {
+ sk_bzero(fMat, sizeof(fMat));
+ fMat[0][0] = fMat[1][1] = fMat[2][2] = fMat[3][3] = 1;
+}
+
+void SkMatrix44::set3x3(SkMScalar m00, SkMScalar m01, SkMScalar m02,
+ SkMScalar m10, SkMScalar m11, SkMScalar m12,
+ SkMScalar m20, SkMScalar m21, SkMScalar m22) {
+ sk_bzero(fMat, sizeof(fMat));
+ fMat[0][0] = m00; fMat[0][1] = m01; fMat[0][2] = m02; fMat[0][3] = 0;
+ fMat[1][0] = m10; fMat[1][1] = m11; fMat[1][2] = m12; fMat[1][3] = 0;
+ fMat[2][0] = m20; fMat[2][1] = m21; fMat[2][2] = m22; fMat[2][3] = 0;
+ fMat[3][0] = 0; fMat[3][1] = 0; fMat[3][2] = 0; fMat[3][3] = 1;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::setTranslate(SkMScalar tx, SkMScalar ty, SkMScalar tz) {
+ this->setIdentity();
+ fMat[3][0] = tx;
+ fMat[3][1] = ty;
+ fMat[3][2] = tz;
+ fMat[3][3] = 1;
+}
+
+void SkMatrix44::preTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz) {
+ SkMatrix44 mat;
+ mat.setTranslate(dx, dy, dz);
+ this->preConcat(mat);
+}
+
+void SkMatrix44::postTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz) {
+ fMat[3][0] += dx;
+ fMat[3][1] += dy;
+ fMat[3][2] += dz;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::setScale(SkMScalar sx, SkMScalar sy, SkMScalar sz) {
+ sk_bzero(fMat, sizeof(fMat));
+ fMat[0][0] = sx;
+ fMat[1][1] = sy;
+ fMat[2][2] = sz;
+ fMat[3][3] = 1;
+}
+
+void SkMatrix44::preScale(SkMScalar sx, SkMScalar sy, SkMScalar sz) {
+ SkMatrix44 tmp;
+ tmp.setScale(sx, sy, sz);
+ this->preConcat(tmp);
+}
+
+void SkMatrix44::postScale(SkMScalar sx, SkMScalar sy, SkMScalar sz) {
+ for (int i = 0; i < 4; i++) {
+ fMat[i][0] *= sx;
+ fMat[i][1] *= sy;
+ fMat[i][2] *= sz;
+ }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::setRotateAbout(SkMScalar x, SkMScalar y, SkMScalar z,
+ SkMScalar radians) {
+ double len2 = x * x + y * y + z * z;
+ if (len2 != 1) {
+ if (len2 == 0) {
+ this->setIdentity();
+ return;
+ }
+ double scale = 1 / sqrt(len2);
+ x *= scale;
+ y *= scale;
+ z *= scale;
+ }
+ this->setRotateAboutUnit(x, y, z, radians);
+}
+
+void SkMatrix44::setRotateAboutUnit(SkMScalar x, SkMScalar y, SkMScalar z,
+ SkMScalar radians) {
+ double c = cos(radians);
+ double s = sin(radians);
+ double C = 1 - c;
+ double xs = x * s;
+ double ys = y * s;
+ double zs = z * s;
+ double xC = x * C;
+ double yC = y * C;
+ double zC = z * C;
+ double xyC = x * yC;
+ double yzC = y * zC;
+ double zxC = z * xC;
+
+ // if you're looking at wikipedia, remember that we're column major.
+ this->set3x3(x * xC + c, xyC + zs, zxC - ys,
+ xyC - zs, y * yC + c, yzC + xs,
+ zxC + ys, yzC - xs, z * zC + c);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::setConcat(const SkMatrix44& a, const SkMatrix44& b) {
+ SkMScalar result[4][4];
+ for (int i = 0; i < 4; i++) {
+ for (int j = 0; j < 4; j++) {
+ double value = 0;
+ for (int k = 0; k < 4; k++) {
+ value += SkMScalarToDouble(a.fMat[k][i]) * b.fMat[j][k];
+ }
+ result[j][i] = SkDoubleToMScalar(value);
+ }
+ }
+ memcpy(fMat, result, sizeof(result));
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+static inline SkMScalar det2x2(double m00, double m01, double m10, double m11) {
+ return m00 * m11 - m10 * m01;
+}
+
+static inline double det3x3(double m00, double m01, double m02,
+ double m10, double m11, double m12,
+ double m20, double m21, double m22) {
+ return m00 * det2x2(m11, m12, m21, m22) -
+ m10 * det2x2(m01, m02, m21, m22) +
+ m20 * det2x2(m01, m02, m11, m12);
+}
+
+/** We always perform the calculation in doubles, to avoid prematurely losing
+ precision along the way. This relies on the compiler automatically
+ promoting our SkMScalar values to double (if needed).
+ */
+double SkMatrix44::determinant() const {
+ return fMat[0][0] * det3x3(fMat[1][1], fMat[1][2], fMat[1][3],
+ fMat[2][1], fMat[2][2], fMat[2][3],
+ fMat[3][1], fMat[3][2], fMat[3][3]) -
+ fMat[1][0] * det3x3(fMat[0][1], fMat[0][2], fMat[0][3],
+ fMat[2][1], fMat[2][2], fMat[2][3],
+ fMat[3][1], fMat[3][2], fMat[3][3]) +
+ fMat[2][0] * det3x3(fMat[0][1], fMat[0][2], fMat[0][3],
+ fMat[1][1], fMat[1][2], fMat[1][3],
+ fMat[3][1], fMat[3][2], fMat[3][3]) -
+ fMat[3][0] * det3x3(fMat[0][1], fMat[0][2], fMat[0][3],
+ fMat[1][1], fMat[1][2], fMat[1][3],
+ fMat[2][1], fMat[2][2], fMat[2][3]);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+// just picked a small value. not sure how to pick the "right" one
+#define TOO_SMALL_FOR_DETERMINANT (1.e-8)
+
+static inline double dabs(double x) {
+ if (x < 0) {
+ x = -x;
+ }
+ return x;
+}
+
+bool SkMatrix44::invert(SkMatrix44* inverse) const {
+ double det = this->determinant();
+ if (dabs(det) < TOO_SMALL_FOR_DETERMINANT) {
+ return false;
+ }
+ if (NULL == inverse) {
+ return true;
+ }
+
+ // we explicitly promote to doubles to keep the intermediate values in
+ // higher precision (assuming SkMScalar isn't already a double)
+ double m00 = fMat[0][0];
+ double m01 = fMat[0][1];
+ double m02 = fMat[0][2];
+ double m03 = fMat[0][3];
+ double m10 = fMat[1][0];
+ double m11 = fMat[1][1];
+ double m12 = fMat[1][2];
+ double m13 = fMat[1][3];
+ double m20 = fMat[2][0];
+ double m21 = fMat[2][1];
+ double m22 = fMat[2][2];
+ double m23 = fMat[2][3];
+ double m30 = fMat[3][0];
+ double m31 = fMat[3][1];
+ double m32 = fMat[3][2];
+ double m33 = fMat[3][3];
+
+ double tmp[4][4];
+
+ tmp[0][0] = m12*m23*m31 - m13*m22*m31 + m13*m21*m32 - m11*m23*m32 - m12*m21*m33 + m11*m22*m33;
+ tmp[0][1] = m03*m22*m31 - m02*m23*m31 - m03*m21*m32 + m01*m23*m32 + m02*m21*m33 - m01*m22*m33;
+ tmp[0][2] = m02*m13*m31 - m03*m12*m31 + m03*m11*m32 - m01*m13*m32 - m02*m11*m33 + m01*m12*m33;
+ tmp[0][3] = m03*m12*m21 - m02*m13*m21 - m03*m11*m22 + m01*m13*m22 + m02*m11*m23 - m01*m12*m23;
+ tmp[1][0] = m13*m22*m30 - m12*m23*m30 - m13*m20*m32 + m10*m23*m32 + m12*m20*m33 - m10*m22*m33;
+ tmp[1][1] = m02*m23*m30 - m03*m22*m30 + m03*m20*m32 - m00*m23*m32 - m02*m20*m33 + m00*m22*m33;
+ tmp[1][2] = m03*m12*m30 - m02*m13*m30 - m03*m10*m32 + m00*m13*m32 + m02*m10*m33 - m00*m12*m33;
+ tmp[1][3] = m02*m13*m20 - m03*m12*m20 + m03*m10*m22 - m00*m13*m22 - m02*m10*m23 + m00*m12*m23;
+ tmp[2][0] = m11*m23*m30 - m13*m21*m30 + m13*m20*m31 - m10*m23*m31 - m11*m20*m33 + m10*m21*m33;
+ tmp[2][1] = m03*m21*m30 - m01*m23*m30 - m03*m20*m31 + m00*m23*m31 + m01*m20*m33 - m00*m21*m33;
+ tmp[2][2] = m01*m13*m30 - m03*m11*m30 + m03*m10*m31 - m00*m13*m31 - m01*m10*m33 + m00*m11*m33;
+ tmp[2][3] = m03*m11*m20 - m01*m13*m20 - m03*m10*m21 + m00*m13*m21 + m01*m10*m23 - m00*m11*m23;
+ tmp[3][0] = m12*m21*m30 - m11*m22*m30 - m12*m20*m31 + m10*m22*m31 + m11*m20*m32 - m10*m21*m32;
+ tmp[3][1] = m01*m22*m30 - m02*m21*m30 + m02*m20*m31 - m00*m22*m31 - m01*m20*m32 + m00*m21*m32;
+ tmp[3][2] = m02*m11*m30 - m01*m12*m30 - m02*m10*m31 + m00*m12*m31 + m01*m10*m32 - m00*m11*m32;
+ tmp[3][3] = m01*m12*m20 - m02*m11*m20 + m02*m10*m21 - m00*m12*m21 - m01*m10*m22 + m00*m11*m22;
+
+ double invDet = 1.0 / det;
+ for (int i = 0; i < 4; i++) {
+ for (int j = 0; j < 4; j++) {
+ inverse->fMat[i][j] = SkDoubleToMScalar(tmp[i][j] * invDet);
+ }
+ }
+ return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::map(const SkScalar src[4], SkScalar dst[4]) const {
+ SkScalar result[4];
+ for (int i = 0; i < 4; i++) {
+ SkMScalar value = 0;
+ for (int j = 0; j < 4; j++) {
+ value += fMat[j][i] * src[j];
+ }
+ result[i] = value;
+ }
+ memcpy(dst, result, sizeof(result));
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkMatrix44::dump() const {
+ SkDebugf("[%g %g %g %g][%g %g %g %g][%g %g %g %g][%g %g %g %g]\n",
+#if 0
+ fMat[0][0], fMat[0][1], fMat[0][2], fMat[0][3],
+ fMat[1][0], fMat[1][1], fMat[1][2], fMat[1][3],
+ fMat[2][0], fMat[2][1], fMat[2][2], fMat[2][3],
+ fMat[3][0], fMat[3][1], fMat[3][2], fMat[3][3]);
+#else
+ fMat[0][0], fMat[1][0], fMat[2][0], fMat[3][0],
+ fMat[0][1], fMat[1][1], fMat[2][1], fMat[3][1],
+ fMat[0][2], fMat[1][2], fMat[2][2], fMat[3][2],
+ fMat[0][3], fMat[1][3], fMat[2][3], fMat[3][3]);
+#endif
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+static void initFromMatrix(SkMScalar dst[4][4], const SkMatrix& src) {
+ sk_bzero(dst, 16 * sizeof(SkMScalar));
+ dst[0][0] = src[SkMatrix::kMScaleX];
+ dst[1][0] = src[SkMatrix::kMSkewX];
+ dst[3][0] = src[SkMatrix::kMTransX];
+ dst[0][1] = src[SkMatrix::kMSkewY];
+ dst[1][1] = src[SkMatrix::kMScaleY];
+ dst[3][1] = src[SkMatrix::kMTransY];
+ dst[2][2] = dst[3][3] = 1;
+}
+
+SkMatrix44::SkMatrix44(const SkMatrix& src) {
+ initFromMatrix(fMat, src);
+}
+
+SkMatrix44& SkMatrix44::operator=(const SkMatrix& src) {
+ initFromMatrix(fMat, src);
+ return *this;
+}
+
+SkMatrix44::operator SkMatrix() const {
+ SkMatrix dst;
+ dst.reset(); // setup our perspective correctly for identity
+
+ dst[SkMatrix::kMScaleX] = SkMScalarToFloat(fMat[0][0]);
+ dst[SkMatrix::kMSkewX] = SkMScalarToFloat(fMat[1][0]);
+ dst[SkMatrix::kMTransX] = SkMScalarToFloat(fMat[3][0]);
+
+ dst[SkMatrix::kMSkewY] = SkMScalarToFloat(fMat[0][1]);
+ dst[SkMatrix::kMScaleY] = SkMScalarToFloat(fMat[1][1]);
+ dst[SkMatrix::kMTransY] = SkMScalarToFloat(fMat[3][1]);
+
+ return dst;
+}
+
+
+