[Bf-committers] Align view to edge (rotate about edge)

[Campbell Barton]

Hi, Hers a small addision to editmesh_mods.c that allows aligning teh 
view to an edge. (2 verts) - see the last ~12 lines.
It seems trivial, but at the moment there is no easy way to rotate 
around an edge- with this- "Align to view" & "Constrain transform to 
view" - could be used to rotate about en edge.
Zr- do you own this module? - is it worth writing a patch?
- Cam

____________
void editmesh_align_view_to_selected(View3D *v3d, int axis)
{
    EditMesh *em = G.editMesh;
    int nselverts= EM_nvertices_selected();

    if (nselverts<2) {
        if (nselverts==0) {
            error("No faces or vertices selected.");
        } else {
            error("At least one face or three vertices must be selected.");
        }
    } else if (EM_nfaces_selected()) {
        float norm[3];
        EditFace *efa;

        norm[0]= norm[1]= norm[2]= 0.0;
        for (efa= em->faces.first; efa; efa= efa->next) {
            if (faceselectedAND(efa, SELECT)) {
                float fno[3];
                if (efa->v4) CalcNormFloat4(efa->v1->co, efa->v2->co, 
efa->v3->co, efa->v4->co, fno);
                else CalcNormFloat(efa->v1->co, efa->v2->co, 
efa->v3->co, fno);
                        /* XXX, fixme, should be flipped intp a
                         * consistent direction. -zr
                         */
                norm[0]+= fno[0];
                norm[1]+= fno[1];
                norm[2]+= fno[2];
            }
        }

        Mat4Mul3Vecfl(G.obedit->obmat, norm);
        view3d_align_axis_to_vector(v3d, axis, norm);
    } else if (nselverts>2) {
        float cent[3], norm[3];
        EditVert *eve, *leve= NULL;

        norm[0]= norm[1]= norm[2]= 0.0;
        editmesh_calc_selvert_center(cent);
        for (eve= em->verts.first; eve; eve= eve->next) {
            if (eve->f & SELECT) {
                if (leve) {
                    float tno[3];
                    CalcNormFloat(cent, leve->co, eve->co, tno);
                   
                        /* XXX, fixme, should be flipped intp a
                         * consistent direction. -zr
                         */
                    norm[0]+= tno[0];
                    norm[1]+= tno[1];
                    norm[2]+= tno[2];
                }
                leve= eve;
            }
        }

        Mat4Mul3Vecfl(G.obedit->obmat, norm);
        view3d_align_axis_to_vector(v3d, axis, norm);
    } else { /* Align view to edge (or 2 verts) */
        float norm[3];
        EditVert *eve, *leve= NULL;

        norm[0]= norm[1]= norm[2]= 0.0;
        for (eve= em->verts.first; eve; eve= eve->next) {
            if (eve->f & SELECT) {
                if (leve) {
                    norm[0]= leve->co[0] - eve->co[0];
                    norm[1]= leve->co[1] - eve->co[1];
                    norm[2]= leve->co[2] - eve->co[2];
                }
                leve= eve;
            }
        }
        Mat4Mul3Vecfl(G.obedit->obmat, norm);
        view3d_align_axis_to_vector(v3d, axis, norm);
    }
}

-- 
Campbell J Barton

133 Hope Street
Geelong West, Victoria 3218 Australia

URL:    http://www.metavr.com
e-mail: cbarton at metavr.com
phone: AU (03) 5229 0241