package edu.berkeley.qfat.geom;
+import javax.media.opengl.*;
// FEATURE: precompute/cache determinant?
/** the identity matrix */
public static final Matrix NEGATIVE_ONE = new Matrix(-1,0,0,0,0,-1,0,0,0,0,-1,0,0,0,0,1);
+ public Matrix(double a, double b, double c, double d, double e, double f, double g,
+ double h, double i, double j, double k, double l, double m, double n, double o, double p) {
+ this((float)a, (float)b, (float)c, (float)d,
+ (float)e, (float)f, (float)g, (float)h,
+ (float)i, (float)j, (float)k, (float)l,
+ (float)m, (float)n, (float)o, (float)p);
+ }
+
public Matrix(float a, float b, float c, float d, float e, float f, float g,
float h, float i, float j, float k, float l, float m, float n, float o, float p) {
this.a = a; this.b = b; this.c = c; this.d = d; this.e = e; this.f = f; this.g = g; this.h = h; this.i = i;
/** discards bottom row */
public Point times(Point p) {
// discards bottom row
- return new Point(a*p.x + b*p.y + c*p.z + d,
- e*p.x + f*p.y + g*p.z + h,
- i*p.x + j*p.y + k*p.z + l);
+ double x = a*p.x + b*p.y + c*p.z + d;
+ double y = e*p.x + f*p.y + g*p.z + h;
+ double z = i*p.x + j*p.y + k*p.z + l;
+ double q = m*p.x + n*p.y + o*p.z + this.p;
+ return new Point(x/q, y/q, z/q);
}
/** discards bottom row */
Float.floatToIntBits(o) ^
Float.floatToIntBits(p);
}
+
+ public static Matrix getProjectionMatrix(GL gl) {
+ int view[] = new int[4];
+ double mvmatrix[] = new double[16];
+ double projmatrix[] = new double[16];
+ gl.glGetIntegerv(GL.GL_VIEWPORT, view, 0);
+ gl.glGetDoublev(GL.GL_MODELVIEW_MATRIX, mvmatrix, 0);
+ gl.glGetDoublev(GL.GL_PROJECTION_MATRIX, projmatrix, 0);
+ Matrix m = new Matrix(mvmatrix[0],
+ mvmatrix[4],
+ mvmatrix[8],
+ mvmatrix[12],
+ mvmatrix[1],
+ mvmatrix[5],
+ mvmatrix[9],
+ mvmatrix[13],
+ mvmatrix[2],
+ mvmatrix[6],
+ mvmatrix[10],
+ mvmatrix[14],
+ mvmatrix[3],
+ mvmatrix[7],
+ mvmatrix[11],
+ mvmatrix[15]);
+ Matrix p = new Matrix(projmatrix[0],
+ projmatrix[4],
+ projmatrix[8],
+ projmatrix[12],
+ projmatrix[1],
+ projmatrix[5],
+ projmatrix[9],
+ projmatrix[13],
+ projmatrix[2],
+ projmatrix[6],
+ projmatrix[10],
+ projmatrix[14],
+ projmatrix[3],
+ projmatrix[7],
+ projmatrix[11],
+ projmatrix[15]);
+ Matrix z =
+ new Matrix(0.5*view[2], 0, 0, view[0]+view[2]*0.5,
+ 0, 0.5*view[3], 0, view[1]+view[3]*0.5,
+ 0, 0, 0.5, 0.5,
+ 0, 0, 0, 1);
+ return z.times(p).times(m);
+ }
+
}