From 872057a46027b4e5609ca0828f8fc2c465d4ada0 Mon Sep 17 00:00:00 2001
From: "reed@android.com"
 <reed@android.com@2bbb7eff-a529-9590-31e7-b0007b416f81>
Date: Wed, 27 Jan 2010 01:45:16 +0000
Subject: [PATCH] add new experimental matrix

git-svn-id: http://skia.googlecode.com/svn/trunk@483 2bbb7eff-a529-9590-31e7-b0007b416f81
---
 experimental/SkMatrix44.cpp | 99 +++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100644 experimental/SkMatrix44.cpp

diff --git a/experimental/SkMatrix44.cpp b/experimental/SkMatrix44.cpp
new file mode 100644
index 000000000..bbc500281
--- /dev/null
+++ b/experimental/SkMatrix44.cpp
@@ -0,0 +1,99 @@
+
+typedef float SkMScalar;
+static const SkMScalar SK_MScalar1 = 1;
+
+struct SkVector4 {
+	SkScalar fData[4];
+};
+
+class SkMatrix44 {
+public:
+	SkMatrix44();
+	explicit SkMatrix44(const SkMatrix44&);
+	SkMatrix44(const SkMatrix44& a, const SkMatrix44& b);
+
+	void setIdentity();
+	void setTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
+	void preTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
+	void postTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
+	void setConcat(const SkMatrix44& a, const SkMatrix44& b);
+
+	void map(const SkScalar src[4], SkScalar dst[4]);
+
+	SkVector4 operator*(const SkVector4& src) {
+		SkVector4 dst;
+		this->map(src.fData, dst.fData);
+		return dst;
+	}
+
+	friend SkMatrix44* operator*(const SkMatrix44& a, const SkMatrix44& b) {
+		return SkMatrix(a, b);
+	}
+
+private:
+	SkMScalar fMat[4][4];
+};
+
+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);
+}
+
+void SkMatrix44:setIdentity() {
+	sk_bzero(fMat, sizeof(fMat));
+	fMat[0][0] = fMat[1][1] = fMat[2][2] = fMat[3][3] = SK_MScalar1;
+}
+
+void SkMatrix44::setTranslate(SkMScalar tx, SkMScalar ty, SkMScalar tz) {
+	sk_bzero(fMat, sizeof(fMat));
+	fMat[3][0] = tx;
+	fMat[3][1] = ty;
+	fMat[3][2] = tz;
+	fMat[3][3] = SK_MScalar1;
+}
+
+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::map(const SkScalar src[4], SkScalar dst[4]) {
+	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::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++) {
+			SkMScalar value = 0;
+			for (int k = 0; k < 4; k++) {
+				value += a.fMat[k][j] * b.fMat[i][k];
+			}
+			result[j][i] = value;
+		}
+	}
+	memcpy(fMat, result, sizeof(result));
+}
+