improvement to scaling gizmo

[mustcode]

here's a way to not have the scaling gizmo always snap to zero scale when user start scaling non-uniformly

            if (m_ScaleType == SCALE_XYZ)
            {
                int difx = x - m_LockX;
                float lng2 = 1.0f + ( float(difx) / 200.0f);
                SnapScale(lng2);
                scVect *=lng2;
            }
            else
            {
                int difx = x - m_LockX;
                int dify = y - m_LockY;

                // modification start ////////////////////////////////////////////////////

                // original code...
                //float len = sqrtf( (float)(difx*difx) + (float)(dify*dify) );
                //float lng2 = len /100.f;

                // get location of object in screen space
                tmatrix viewproj = m_Model * m_Proj;
                tvector3 trans = m_pMatrix->GetTranslation();
                tvector4 wpos = vector4(trans.x, trans.y, trans.z, 1.f);
                wpos.Transform(viewproj);
                tvector2 spos(wpos.x/wpos.w, -(wpos.y/wpos.w));
                if(wpos.z < 0)
                    return;
                tvector2 screenPos(0,0);
                tvector2 screenSize((float)mScreenWidth, (float)mScreenHeight);
                tvector2 pos(screenPos.x + (1.f + spos.x)*(screenSize.x * .5f), (screenPos.y + (1.f + spos.y)*(screenSize.y * .5f)));

                // compare clicked pos and object pos to choose between x or y axis
                // and determine which direction is positive or negative
                float lng2;
                float distx = abs(m_LockX - pos.x);
                float disty = abs(m_LockY - pos.y);
                if(distx >= disty)
                {
                    if(m_LockX < pos.x)
                        lng2 = 1.0f - ( float(difx) / 100.0f);
                    else
                        lng2 = 1.0f + ( float(difx) / 100.0f);
                }
                else
                {
                    if(m_LockY < pos.y)
                        lng2 = 1.0f - ( float(dify) / 100.0f);
                    else
                        lng2 = 1.0f + ( float(dify) / 100.0f);
                }
                // modification end //////////////////////////////////////////////////////

                /*
                float lng2 = ( df.Dot(m_LockVertex));
                char tmps[512];
                sprintf(tmps, "%5.4f\n", lng2 );
                OutputDebugStringA( tmps );


                if (lng2 < 1.f)
                {
                    if ( lng2<= 0.001f )
                        lng2 = 0.001f;
                    else
                    {
                        //lng2+=4.f;
                        lng2/=5.f;
                    }
                }
                else
                {
                    int a = 1;
                }
                */
                SnapScale(lng2);
                scVect *= lng2;
                scVect += scVect2;
            }