/**
* Calculate a 3d segment from 2d window coordinates.
* This ray_start is located at the viewpoint, ray_end is a far point.
* ray_start and ray_end are clipped by the view near and far limits
* so points along this line are always in view.
* In orthographic view all resulting segments will be parallel.
* \param ar The region (used for the window width and height).
* \param v3d The 3d viewport (used for near and far clipping range).
* \param mval The area relative 2d location (such as event->mval, converted into float[2]).
* \param ray_start The world-space starting point of the segment.
* \param ray_end The world-space end point of the segment.
* \return success, FALSE if the segment is totally clipped.
*/
int ED_view3d_win_to_segment_clip(ARegion *ar, View3D *v3d, const float mval[2], float ray_start[3], float ray_end[3])
{
RegionView3D *rv3d = ar->regiondata;
ED_view3d_win_to_segment(ar, v3d, mval, ray_start, ray_end);
/* clipping */
if (rv3d->rflag & RV3D_CLIPPING) {
/* if the ray is totally clipped,
* restore the original values but return FALSE
* caller can choose what to do */
float tray_start[3] = {UNPACK3(ray_start)};
float tray_end[3] = {UNPACK3(ray_end)};
int a;
for (a = 0; a < 4; a++) {
if (clip_line_plane(tray_start, tray_end, rv3d->clip[a]) == FALSE) {
return FALSE;
}
}
/* copy in clipped values */
copy_v3_v3(ray_start, tray_start);
copy_v3_v3(ray_end, tray_end);
}
return TRUE;
}
/* create intersection coordinates in view Z direction at mouse coordinates */
void ED_view3d_win_to_segment_clip(ARegion *ar, View3D *v3d, const float mval[2], float ray_start[3], float ray_end[3])
{
RegionView3D *rv3d= ar->regiondata;
if(rv3d->is_persp) {
float vec[3];
ED_view3d_win_to_vector(ar, mval, vec);
copy_v3_v3(ray_start, rv3d->viewinv[3]);
madd_v3_v3v3fl(ray_start, rv3d->viewinv[3], vec, v3d->near);
madd_v3_v3v3fl(ray_end, rv3d->viewinv[3], vec, v3d->far);
}
else {
float vec[4];
vec[0] = 2.0f * mval[0] / ar->winx - 1;
vec[1] = 2.0f * mval[1] / ar->winy - 1;
vec[2] = 0.0f;
vec[3] = 1.0f;
mul_m4_v4(rv3d->persinv, vec);
madd_v3_v3v3fl(ray_start, vec, rv3d->viewinv[2], 1000.0f);
madd_v3_v3v3fl(ray_end, vec, rv3d->viewinv[2], -1000.0f);
}
/* clipping */
if(rv3d->rflag & RV3D_CLIPPING) {
int a;
for(a=0; a<4; a++) {
clip_line_plane(ray_start, ray_end, rv3d->clip[a]);
}
}
}
