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MATH: Simplify gluMathUnProject

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Bastien Bouclet 2015-03-22 13:24:03 +01:00
parent 23da0ef0c3
commit 6f47c5fbf3
2 changed files with 27 additions and 36 deletions
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24
math/glmath.cpp
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@ -24,6 +24,30 @@
namespace Math {
// function based on gluUnProject from Mesa 5.0 glu GPLv2+ licensed sources
bool gluMathUnProject(Vector3d win, const Matrix4 &mvpMatrix, const Common::Rect &viewport, Vector3d &obj) {
Matrix4 A;
Vector4d in, out;
in.x() = (win.x() - viewport.left) * 2 / viewport.width() - 1.0;
in.y() = (win.y() - viewport.top) * 2 / viewport.height() - 1.0;
in.z() = 2 * win.z() - 1.0;
in.w() = 1.0;
A = mvpMatrix;
A.inverse();
out = A.transform(in);
if (out.w() == 0.0)
return false;
obj.x() = out.x() / out.w();
obj.y() = out.y() / out.w();
obj.z() = out.z() / out.w();
return true;
}
// function based on gluPerspective from Mesa 5.0 glu GPLv2+ licensed sources
Matrix4 makePerspectiveMatrix(double fovy, double aspect, double zNear, double zFar) {
double xmin, xmax, ymin, ymax;