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Java Source | 1997-09-10 | 4.6 KB | 200 lines |
-
- /** A fairly conventional 3D matrix object that can transform sets of
- 3D points and perform a variety of manipulations on the transform */
-
- package sunw.demo.molecule;
-
- class Matrix3D {
- float xx, xy, xz, xo;
- float yx, yy, yz, yo;
- float zx, zy, zz, zo;
- static final double pi = 3.14159265;
- /** Create a new unit matrix */
- Matrix3D () {
- xx = 1.0f;
- yy = 1.0f;
- zz = 1.0f;
- }
- /** Scale by f in all dimensions */
- void scale(float f) {
- xx *= f;
- xy *= f;
- xz *= f;
- xo *= f;
- yx *= f;
- yy *= f;
- yz *= f;
- yo *= f;
- zx *= f;
- zy *= f;
- zz *= f;
- zo *= f;
- }
- /** Scale along each axis independently */
- void scale(float xf, float yf, float zf) {
- xx *= xf;
- xy *= xf;
- xz *= xf;
- xo *= xf;
- yx *= yf;
- yy *= yf;
- yz *= yf;
- yo *= yf;
- zx *= zf;
- zy *= zf;
- zz *= zf;
- zo *= zf;
- }
- /** Translate the origin */
- void translate(float x, float y, float z) {
- xo += x;
- yo += y;
- zo += z;
- }
- /** rotate theta degrees about the y axis */
- void yrot(double theta) {
- theta *= (pi / 180);
- double ct = Math.cos(theta);
- double st = Math.sin(theta);
-
- float Nxx = (float) (xx * ct + zx * st);
- float Nxy = (float) (xy * ct + zy * st);
- float Nxz = (float) (xz * ct + zz * st);
- float Nxo = (float) (xo * ct + zo * st);
-
- float Nzx = (float) (zx * ct - xx * st);
- float Nzy = (float) (zy * ct - xy * st);
- float Nzz = (float) (zz * ct - xz * st);
- float Nzo = (float) (zo * ct - xo * st);
-
- xo = Nxo;
- xx = Nxx;
- xy = Nxy;
- xz = Nxz;
- zo = Nzo;
- zx = Nzx;
- zy = Nzy;
- zz = Nzz;
- }
- /** rotate theta degrees about the x axis */
- void xrot(double theta) {
- theta *= (pi / 180);
- double ct = Math.cos(theta);
- double st = Math.sin(theta);
-
- float Nyx = (float) (yx * ct + zx * st);
- float Nyy = (float) (yy * ct + zy * st);
- float Nyz = (float) (yz * ct + zz * st);
- float Nyo = (float) (yo * ct + zo * st);
-
- float Nzx = (float) (zx * ct - yx * st);
- float Nzy = (float) (zy * ct - yy * st);
- float Nzz = (float) (zz * ct - yz * st);
- float Nzo = (float) (zo * ct - yo * st);
-
- yo = Nyo;
- yx = Nyx;
- yy = Nyy;
- yz = Nyz;
- zo = Nzo;
- zx = Nzx;
- zy = Nzy;
- zz = Nzz;
- }
- /** rotate theta degrees about the z axis */
- void zrot(double theta) {
- theta *= (pi / 180);
- double ct = Math.cos(theta);
- double st = Math.sin(theta);
-
- float Nyx = (float) (yx * ct + xx * st);
- float Nyy = (float) (yy * ct + xy * st);
- float Nyz = (float) (yz * ct + xz * st);
- float Nyo = (float) (yo * ct + xo * st);
-
- float Nxx = (float) (xx * ct - yx * st);
- float Nxy = (float) (xy * ct - yy * st);
- float Nxz = (float) (xz * ct - yz * st);
- float Nxo = (float) (xo * ct - yo * st);
-
- yo = Nyo;
- yx = Nyx;
- yy = Nyy;
- yz = Nyz;
- xo = Nxo;
- xx = Nxx;
- xy = Nxy;
- xz = Nxz;
- }
- /** Multiply this matrix by a second: M = M*R */
- void mult(Matrix3D rhs) {
- float lxx = xx * rhs.xx + yx * rhs.xy + zx * rhs.xz;
- float lxy = xy * rhs.xx + yy * rhs.xy + zy * rhs.xz;
- float lxz = xz * rhs.xx + yz * rhs.xy + zz * rhs.xz;
- float lxo = xo * rhs.xx + yo * rhs.xy + zo * rhs.xz + rhs.xo;
-
- float lyx = xx * rhs.yx + yx * rhs.yy + zx * rhs.yz;
- float lyy = xy * rhs.yx + yy * rhs.yy + zy * rhs.yz;
- float lyz = xz * rhs.yx + yz * rhs.yy + zz * rhs.yz;
- float lyo = xo * rhs.yx + yo * rhs.yy + zo * rhs.yz + rhs.yo;
-
- float lzx = xx * rhs.zx + yx * rhs.zy + zx * rhs.zz;
- float lzy = xy * rhs.zx + yy * rhs.zy + zy * rhs.zz;
- float lzz = xz * rhs.zx + yz * rhs.zy + zz * rhs.zz;
- float lzo = xo * rhs.zx + yo * rhs.zy + zo * rhs.zz + rhs.zo;
-
- xx = lxx;
- xy = lxy;
- xz = lxz;
- xo = lxo;
-
- yx = lyx;
- yy = lyy;
- yz = lyz;
- yo = lyo;
-
- zx = lzx;
- zy = lzy;
- zz = lzz;
- zo = lzo;
- }
-
- /** Reinitialize to the unit matrix */
- void unit() {
- xo = 0;
- xx = 1;
- xy = 0;
- xz = 0;
- yo = 0;
- yx = 0;
- yy = 1;
- yz = 0;
- zo = 0;
- zx = 0;
- zy = 0;
- zz = 1;
- }
- /** Transform nvert points from v into tv. v contains the input
- coordinates in floating point. Three successive entries in
- the array constitute a point. tv ends up holding the transformed
- points as integers; three successive entries per point */
- void transform(float v[], int tv[], int nvert) {
- float lxx = xx, lxy = xy, lxz = xz, lxo = xo;
- float lyx = yx, lyy = yy, lyz = yz, lyo = yo;
- float lzx = zx, lzy = zy, lzz = zz, lzo = zo;
- for (int i = nvert * 3; (i -= 3) >= 0;) {
- float x = v[i];
- float y = v[i + 1];
- float z = v[i + 2];
- tv[i ] = (int) (x * lxx + y * lxy + z * lxz + lxo);
- tv[i + 1] = (int) (x * lyx + y * lyy + z * lyz + lyo);
- tv[i + 2] = (int) (x * lzx + y * lzy + z * lzz + lzo);
- }
- }
- public String toString() {
- return ("[" + xo + "," + xx + "," + xy + "," + xz + ";"
- + yo + "," + yx + "," + yy + "," + yz + ";"
- + zo + "," + zx + "," + zy + "," + zz + "]");
- }
- }
-