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[Solved]Picking system

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[Solved]Picking system
« on: January 23, 2018, 10:55:50 »
hi,
I've a problem with picking in 3d that's my code to get ray
Code: [Select]
public class Mouse3D {

private static Vector3f ray;

public static Vector3f GetRay() {
Vector2f normlizedCoords = toNormlizedDeviceCoords(Mouse.GetMosuePos());
Vector4f clipCoords = new Vector4f(normlizedCoords.x, normlizedCoords.y,
-1, 1);
Vector4f eyeCoords = toEyeCoords(clipCoords);
ray = toWorldCoords(eyeCoords);
return ray;
}

private static Vector2f toNormlizedDeviceCoords(Vector2f mousePos) {
Vector2f pos = new Vector2f();
pos.x = (float) ((2 * mousePos.x) / Main.getWidth() - 1);
pos.y = (float) ((2 * mousePos.y) / Main.getHeigth() - 1);
return pos;
}

private static Vector4f toEyeCoords(Vector4f clipCoords) {
Matrix4f invertedProjection = View.getPm().invert();
Vector4f eyeCoords = new Vector4f();
invertedProjection.transform(clipCoords.x, clipCoords.y, clipCoords.z,
clipCoords.w, eyeCoords);
return new Vector4f((float) eyeCoords.x, (float) eyeCoords.y, -1, 1);
}

private static Vector3f toWorldCoords(Vector4f eyeCoords) {
Matrix4f InvertedView = View.getVm().invert();
Vector4f Ray = new Vector4f();
InvertedView.transform(eyeCoords.x, eyeCoords.y, eyeCoords.z,
eyeCoords.w, Ray);
return new Vector3f((float) Ray.x, (float) Ray.y, (float) Ray.z)
.normalize();
}

}
and parts of my View class
Code: [Select]
public static void go3D() {
rotR = (float) Math.toRadians(rotD);
camX = (float) Math.cos(rotR) * zom + posX;
camZ = (float) Math.sin(rotR) * zom + posZ;
camY = posY + zom * 2;
enable3D();
viewMatrix.identity();
pm = viewMatrix.setPerspective((float) Math.toRadians(FOV), ASPECT,
NEAR, FAR);
glMatrixMode(GL_PROJECTION);
glLoadMatrixf(viewMatrix.get(fb));
vm = viewMatrix.setLookAt(camX, camY, camZ, posX, posY, posZ, 0, 1, 0);
glMatrixMode(GL_MODELVIEW);
glLoadMatrixf(viewMatrix.get(fb));
}
private static void enable3D() {
if (WIREFRAME)
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
glDisable(GL_TEXTURE_2D);
glEnable(GL_DEPTH_TEST);
glEnable(GL_SHADE_MODEL);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_NORMALIZE);
glEnable(GL_COLOR_MATERIAL);
glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
glShadeModel(GL_FLAT);
glClearDepth(1);
}
« Last Edit: January 23, 2018, 15:53:22 by Andrew Alfazy »

*

Offline KaiHH

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Re: Picking system
« Reply #1 on: January 23, 2018, 11:27:56 »
Since it looks like you are using JOML, there is a much shorter way to obtain the world-space ray of the mouse pointer. Please see Matrix4f.unprojectRay(). It is equivalent to two invocations of GLU's gluUnproject() with the near and far plane Z coordinate to compute a ray instead of a point in 3D. The matrix to call this method on must be the uninverted combined view-projection matrix.
« Last Edit: January 23, 2018, 18:41:25 by KaiHH »

Re: Picking system
« Reply #2 on: January 23, 2018, 15:43:29 »
thanks very much,I can't believe it is working very good! :o