//沿Y轴旋转degree角度
void CSpriteEx::rotateY(float degree)
{
static float fRadSeed = 3.14159f/180.0f;
//创建个旋转矩阵
kmMat4 kMat;
kmMat4Identity(&kMat);
kmMat4RotationY(&kMat, degree*fRadSeed);
Vertex3F* v[4] = {&_quad.bl.vertices, &_quad.br.vertices, &_quad.tl.vertices, &_quad.tr.vertices};
Vertex3F* vOri[4] = {&m_sQuadOri.bl.vertices, &m_sQuadOri.br.vertices, &m_sQuadOri.tl.vertices, &m_sQuadOri.tr.vertices};
//向量矩阵相乘
for(int i = 0; i < 4; ++i) {
float x = kMat.mat[0]*vOri[i]->x + kMat.mat[4]*vOri[i]->y + kMat.mat[8]*vOri[i]->z + kMat.mat[12];
float y = kMat.mat[1]*vOri[i]->x + kMat.mat[5]*vOri[i]->y + kMat.mat[9]*vOri[i]->z + kMat.mat[13];
float z = kMat.mat[2]*vOri[i]->x + kMat.mat[6]*vOri[i]->y + kMat.mat[10]*vOri[i]->z + kMat.mat[14];
v[i]->x = x;
v[i]->y = y;
v[i]->z = z;
}
}
const kmMat4& Node::getNodeToParentTransform() const
{
if (_transformDirty)
{
// Translate values
float x = _position.x;
float y = _position.y;
float z = _positionZ;
if (_ignoreAnchorPointForPosition)
{
x += _anchorPointInPoints.x;
y += _anchorPointInPoints.y;
}
// Rotation values
// Change rotation code to handle X and Y
// If we skew with the exact same value for both x and y then we're simply just rotating
float cx = 1, sx = 0, cy = 1, sy = 0;
if (_rotationZ_X || _rotationZ_Y)
{
float radiansX = -CC_DEGREES_TO_RADIANS(_rotationZ_X);
float radiansY = -CC_DEGREES_TO_RADIANS(_rotationZ_Y);
cx = cosf(radiansX);
sx = sinf(radiansX);
cy = cosf(radiansY);
sy = sinf(radiansY);
}
bool needsSkewMatrix = ( _skewX || _skewY );
// optimization:
// inline anchor point calculation if skew is not needed
// Adjusted transform calculation for rotational skew
if (! needsSkewMatrix && !_anchorPointInPoints.equals(Point::ZERO))
{
x += cy * -_anchorPointInPoints.x * _scaleX + -sx * -_anchorPointInPoints.y * _scaleY;
y += sy * -_anchorPointInPoints.x * _scaleX + cx * -_anchorPointInPoints.y * _scaleY;
}
// Build Transform Matrix
// Adjusted transform calculation for rotational skew
kmScalar mat[] = {
cy * _scaleX, sy * _scaleX, 0, 0,
-sx * _scaleY, cx * _scaleY, 0, 0,
0, 0, _scaleZ, 0,
x, y, z, 1 };
kmMat4Fill(&_transform, mat);
// XXX
// FIX ME: Expensive operation.
// FIX ME: It should be done together with the rotationZ
if(_rotationY) {
kmMat4 rotY;
kmMat4RotationY(&rotY,CC_DEGREES_TO_RADIANS(_rotationY));
kmMat4Multiply(&_transform, &_transform, &rotY);
}
if(_rotationX) {
kmMat4 rotX;
kmMat4RotationX(&rotX,CC_DEGREES_TO_RADIANS(_rotationX));
kmMat4Multiply(&_transform, &_transform, &rotX);
}
// XXX: Try to inline skew
// If skew is needed, apply skew and then anchor point
if (needsSkewMatrix)
{
kmMat4 skewMatrix = { 1, (float)tanf(CC_DEGREES_TO_RADIANS(_skewY)), 0, 0,
(float)tanf(CC_DEGREES_TO_RADIANS(_skewX)), 1, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1};
kmMat4Multiply(&_transform, &_transform, &skewMatrix);
// adjust anchor point
if (!_anchorPointInPoints.equals(Point::ZERO))
{
// XXX: Argh, kmMat needs a "translate" method.
// XXX: Although this is faster than multiplying a vec4 * mat4
_transform.mat[12] += _transform.mat[0] * -_anchorPointInPoints.x + _transform.mat[4] * -_anchorPointInPoints.y;
_transform.mat[13] += _transform.mat[1] * -_anchorPointInPoints.x + _transform.mat[5] * -_anchorPointInPoints.y;
}
}
if (_useAdditionalTransform)
{
kmMat4Multiply(&_transform, &_transform, &_additionalTransform);
}
_transformDirty = false;
}
return _transform;
}
