blender-archive/source/blender/src/transform_snap.c

/**
 * $Id: 
 *
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): Martin Poirier
 *
 * ***** END GPL LICENSE BLOCK *****
 */
 
#include <stdlib.h>
#include <math.h>
#include <stdio.h>

#include "PIL_time.h"

#include "DNA_armature_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_meshdata_types.h" // Temporary, for snapping to other unselected meshes
#include "DNA_space_types.h"
#include "DNA_screen_types.h"
#include "DNA_userdef_types.h"
#include "DNA_view3d_types.h"

#include "BLI_arithb.h"
#include "BLI_editVert.h"
#include "BLI_blenlib.h"

#include "BDR_drawobject.h"

#include "editmesh.h"
#include "BIF_editsima.h"
#include "BIF_gl.h"
#include "BIF_glutil.h"
#include "BIF_mywindow.h"
#include "BIF_resources.h"
#include "BIF_screen.h"
#include "BIF_editsima.h"
#include "BIF_drawimage.h"
#include "BIF_editmesh.h"

#include "BIF_transform.h"

#include "BKE_global.h"
#include "BKE_utildefines.h"
#include "BKE_DerivedMesh.h"
#include "BKE_object.h"
#include "BKE_anim.h" /* for duplis */

#include "BSE_view.h"

#include "MEM_guardedalloc.h"

#include "transform.h"
#include "mydevice.h"		/* for KEY defines	*/
#include "blendef.h" /* for selection modes */

/********************* PROTOTYPES ***********************/

void setSnappingCallback(TransInfo *t);

void ApplySnapTranslation(TransInfo *t, float vec[3]);
void ApplySnapRotation(TransInfo *t, float *vec);
void ApplySnapResize(TransInfo *t, float *vec);

void CalcSnapGrid(TransInfo *t, float *vec);
void CalcSnapGeometry(TransInfo *t, float *vec);

void TargetSnapMedian(TransInfo *t);
void TargetSnapCenter(TransInfo *t);
void TargetSnapClosest(TransInfo *t);
void TargetSnapActive(TransInfo *t);

float RotationBetween(TransInfo *t, float p1[3], float p2[3]);
float TranslationBetween(TransInfo *t, float p1[3], float p2[3]);
float ResizeBetween(TransInfo *t, float p1[3], float p2[3]);


/****************** IMPLEMENTATIONS *********************/

int BIF_snappingSupported(void)
{
	int status = 0;
	
	if (G.obedit == NULL || ELEM(G.obedit->type, OB_MESH, OB_ARMATURE)) /* only support object, mesh, armature */
	{
		status = 1;
	}
	
	return status;
}

void drawSnapping(TransInfo *t)
{
	if ((t->tsnap.status & (SNAP_ON|POINT_INIT|TARGET_INIT)) == (SNAP_ON|POINT_INIT|TARGET_INIT) &&
		(G.qual & LR_CTRLKEY)) {
		
		char col[4];
		BIF_GetThemeColor3ubv(TH_TRANSFORM, col);
		glColor4ub(col[0], col[1], col[2], 128);
		
		if (t->spacetype==SPACE_VIEW3D) {
			float unitmat[4][4];
			float size;
			
			glDisable(GL_DEPTH_TEST);
	
			size = get_drawsize(G.vd, t->tsnap.snapPoint);
			
			size *= 0.5f * BIF_GetThemeValuef(TH_VERTEX_SIZE);
			
			glPushMatrix();
			
			glTranslatef(t->tsnap.snapPoint[0], t->tsnap.snapPoint[1], t->tsnap.snapPoint[2]);
			
			/* draw normal if needed */
			if (usingSnappingNormal(t) && validSnappingNormal(t))
			{
				glBegin(GL_LINES);
					glVertex3f(0, 0, 0);
					glVertex3f(t->tsnap.snapNormal[0], t->tsnap.snapNormal[1], t->tsnap.snapNormal[2]);
				glEnd();
			}
			
			/* sets view screen aligned */
			glRotatef( -360.0f*saacos(G.vd->viewquat[0])/(float)M_PI, G.vd->viewquat[1], G.vd->viewquat[2], G.vd->viewquat[3]);
			
			Mat4One(unitmat);
			drawcircball(GL_LINE_LOOP, unitmat[3], size, unitmat);
			
			glPopMatrix();
			
			if(G.vd->zbuf) glEnable(GL_DEPTH_TEST);
		} else if (t->spacetype==SPACE_IMAGE) {
			/*This will not draw, and Im nor sure why - campbell */
			
			/*			
			float xuser_asp, yuser_asp;
			int wi, hi;
			float w, h;
			
			calc_image_view(G.sima, 'f');	// float
			myortho2(G.v2d->cur.xmin, G.v2d->cur.xmax, G.v2d->cur.ymin, G.v2d->cur.ymax);
			glLoadIdentity();
			
			aspect_sima(G.sima, &xuser_asp, &yuser_asp);
			
			transform_width_height_tface_uv(&wi, &hi);
			w = (((float)wi)/256.0f)*G.sima->zoom * xuser_asp;
			h = (((float)hi)/256.0f)*G.sima->zoom * yuser_asp;
			
			cpack(0xFFFFFF);
			glTranslatef(t->tsnap.snapPoint[0], t->tsnap.snapPoint[1], 0.0f);
			
			//glRectf(0,0,1,1);
			
			setlinestyle(0);
			cpack(0x0);
			fdrawline(-0.020/w, 0, -0.1/w, 0);
			fdrawline(0.1/w, 0, .020/w, 0);
			fdrawline(0, -0.020/h, 0, -0.1/h);
			fdrawline(0, 0.1/h, 0, 0.020/h);
			
			glTranslatef(-t->tsnap.snapPoint[0], -t->tsnap.snapPoint[1], 0.0f);
			setlinestyle(0);
			*/
			
		}
	}
}

int  handleSnapping(TransInfo *t, int event)
{
	int status = 0;
	
	if (BIF_snappingSupported() && event == TABKEY && (G.qual & LR_SHIFTKEY) == LR_SHIFTKEY)
	{
		/* toggle snap and reinit */
		G.scene->snap_flag ^= SCE_SNAP;
		initSnapping(t);
		status = 1;
	}
	
	return status;
}

void applySnapping(TransInfo *t, float *vec)
{
	if ((t->tsnap.status & SNAP_ON) &&
		(G.qual & LR_CTRLKEY))
	{
		double current = PIL_check_seconds_timer();
		
		// Time base quirky code to go around findnearest slowness
		/* !TODO! add exception for object mode, no need to slow it down then */
		if (current - t->tsnap.last  >= 0.1)
		{
			t->tsnap.calcSnap(t, vec);
			t->tsnap.targetSnap(t);
	
			t->tsnap.last = current;
		}
		if ((t->tsnap.status & (POINT_INIT|TARGET_INIT)) == (POINT_INIT|TARGET_INIT))
		{
			t->tsnap.applySnap(t, vec);
		}
	}
}

void resetSnapping(TransInfo *t)
{
	t->tsnap.status = 0;
	t->tsnap.modePoint = 0;
	t->tsnap.modeTarget = 0;
	t->tsnap.last = 0;
	t->tsnap.applySnap = NULL;

	t->tsnap.snapNormal[0] = 0;
	t->tsnap.snapNormal[1] = 0;
	t->tsnap.snapNormal[2] = 0;
}

int usingSnappingNormal(TransInfo *t)
{
	if (G.scene->snap_flag & SCE_SNAP_ROTATE)
	{
		return 1;
	}
	else
	{
		return 0;
	}
}

int validSnappingNormal(TransInfo *t)
{
	if ((t->tsnap.status & (POINT_INIT|TARGET_INIT)) == (POINT_INIT|TARGET_INIT))
	{
		if (Inpf(t->tsnap.snapNormal, t->tsnap.snapNormal) > 0)
		{
			return 1;
		}
	}
	
	return 0;
}

void initSnapping(TransInfo *t)
{
	resetSnapping(t);
	
	if ((t->spacetype == SPACE_VIEW3D || t->spacetype == SPACE_IMAGE) && // Only 3D view or UV
			(t->flag & T_CAMERA) == 0) { // Not with camera selected
		setSnappingCallback(t);

		/* Edit mode */
		if (t->tsnap.applySnap != NULL && // A snapping function actually exist
			(G.scene->snap_flag & SCE_SNAP) && // Only if the snap flag is on
			(G.obedit != NULL && ELEM(G.obedit->type, OB_MESH, OB_ARMATURE)) && // Temporary limited to edit mode meshes and armatures
			((t->flag & T_PROP_EDIT) == 0) ) // No PET, obviously
		{
			t->tsnap.status |= SNAP_ON;
			t->tsnap.modePoint = SNAP_GEO;
		}
		/* Object mode */
		else if (t->tsnap.applySnap != NULL && // A snapping function actually exist
			(G.scene->snap_flag & SCE_SNAP) && // Only if the snap flag is on
			(G.obedit == NULL) ) // Object Mode
		{
			t->tsnap.status |= SNAP_ON;
			t->tsnap.modePoint = SNAP_GEO;
		}
		else
		{	
			/* Grid if snap is not possible */
			t->tsnap.modePoint = SNAP_GRID;
		}
	}
	else
	{
		/* Always grid outside of 3D view */
		t->tsnap.modePoint = SNAP_GRID;
	}
}

void setSnappingCallback(TransInfo *t)
{
	t->tsnap.calcSnap = CalcSnapGeometry;

	switch(G.scene->snap_target)
	{
		case SCE_SNAP_TARGET_CLOSEST:
			t->tsnap.modeTarget = SNAP_CLOSEST;
			t->tsnap.targetSnap = TargetSnapClosest;
			break;
		case SCE_SNAP_TARGET_CENTER:
			t->tsnap.modeTarget = SNAP_CENTER;
			t->tsnap.targetSnap = TargetSnapCenter;
			break;
		case SCE_SNAP_TARGET_MEDIAN:
			t->tsnap.modeTarget = SNAP_MEDIAN;
			t->tsnap.targetSnap = TargetSnapMedian;
			break;
		case SCE_SNAP_TARGET_ACTIVE:
			t->tsnap.modeTarget = SNAP_ACTIVE;
			t->tsnap.targetSnap = TargetSnapActive;
			break;

	}

	switch (t->mode)
	{
	case TFM_TRANSLATION:
		t->tsnap.applySnap = ApplySnapTranslation;
		t->tsnap.distance = TranslationBetween;
		break;
	case TFM_ROTATION:
		t->tsnap.applySnap = ApplySnapRotation;
		t->tsnap.distance = RotationBetween;
		
		// Can't do TARGET_CENTER with rotation, use TARGET_MEDIAN instead
		if (G.scene->snap_target == SCE_SNAP_TARGET_CENTER) {
			t->tsnap.modeTarget = SNAP_MEDIAN;
			t->tsnap.targetSnap = TargetSnapMedian;
		}
		break;
	case TFM_RESIZE:
		t->tsnap.applySnap = ApplySnapResize;
		t->tsnap.distance = ResizeBetween;
		
		// Can't do TARGET_CENTER with resize, use TARGET_MEDIAN instead
		if (G.scene->snap_target == SCE_SNAP_TARGET_CENTER) {
			t->tsnap.modeTarget = SNAP_MEDIAN;
			t->tsnap.targetSnap = TargetSnapMedian;
		}
		break;
	default:
		t->tsnap.applySnap = NULL;
		break;
	}
}

/********************** APPLY **************************/

void ApplySnapTranslation(TransInfo *t, float vec[3])
{
	VecSubf(vec, t->tsnap.snapPoint, t->tsnap.snapTarget);
}

void ApplySnapRotation(TransInfo *t, float *vec)
{
	if (t->tsnap.modeTarget == SNAP_CLOSEST) {
		*vec = t->tsnap.dist;
	}
	else {
		*vec = RotationBetween(t, t->tsnap.snapTarget, t->tsnap.snapPoint);
	}
}

void ApplySnapResize(TransInfo *t, float vec[3])
{
	if (t->tsnap.modeTarget == SNAP_CLOSEST) {
		vec[0] = vec[1] = vec[2] = t->tsnap.dist;
	}
	else {
		vec[0] = vec[1] = vec[2] = ResizeBetween(t, t->tsnap.snapTarget, t->tsnap.snapPoint);
	}
}

/********************** DISTANCE **************************/

float TranslationBetween(TransInfo *t, float p1[3], float p2[3])
{
	return VecLenf(p1, p2);
}

float RotationBetween(TransInfo *t, float p1[3], float p2[3])
{
	float angle, start[3], end[3], center[3];
	
	VECCOPY(center, t->center);	
	if(t->flag & (T_EDIT|T_POSE)) {
		Object *ob= G.obedit?G.obedit:t->poseobj;
		Mat4MulVecfl(ob->obmat, center);
	}

	VecSubf(start, p1, center);
	VecSubf(end, p2, center);	
		
	// Angle around a constraint axis (error prone, will need debug)
	if (t->con.applyRot != NULL && (t->con.mode & CON_APPLY)) {
		float axis[3], tmp[3];
		
		t->con.applyRot(t, NULL, axis, NULL);

		Projf(tmp, end, axis);
		VecSubf(end, end, tmp);
		
		Projf(tmp, start, axis);
		VecSubf(start, start, tmp);
		
		Normalize(end);
		Normalize(start);
		
		Crossf(tmp, start, end);
		
		if (Inpf(tmp, axis) < 0.0)
			angle = -acos(Inpf(start, end));
		else	
			angle = acos(Inpf(start, end));
	}
	else {
		float mtx[3][3];
		
		Mat3CpyMat4(mtx, t->viewmat);

		Mat3MulVecfl(mtx, end);
		Mat3MulVecfl(mtx, start);
		
		angle = atan2(start[1],start[0]) - atan2(end[1],end[0]);
	}
	
	if (angle > M_PI) {
		angle = angle - 2 * M_PI;
	}
	else if (angle < -(M_PI)) {
		angle = 2 * M_PI + angle;
	}
	
	return angle;
}

float ResizeBetween(TransInfo *t, float p1[3], float p2[3])
{
	float d1[3], d2[3], center[3];
	
	VECCOPY(center, t->center);	
	if(t->flag & (T_EDIT|T_POSE)) {
		Object *ob= G.obedit?G.obedit:t->poseobj;
		Mat4MulVecfl(ob->obmat, center);
	}

	VecSubf(d1, p1, center);
	VecSubf(d2, p2, center);
	
	if (t->con.applyRot != NULL && (t->con.mode & CON_APPLY)) {
		Mat3MulVecfl(t->con.pmtx, d1);
		Mat3MulVecfl(t->con.pmtx, d2);
	}
	
	return VecLength(d2) / VecLength(d1);
}

/********************** CALC **************************/

void CalcSnapGrid(TransInfo *t, float *vec)
{
	snapGridAction(t, t->tsnap.snapPoint, BIG_GEARS);
}

void CalcSnapGeometry(TransInfo *t, float *vec)
{
	if (t->spacetype == SPACE_VIEW3D)
	{
		float loc[3];
		float no[3];
		int found = 0;
		int dist = 40; // Use a user defined value here
		SnapMode mode;
		
		if (G.scene->snap_mode == SCE_SNAP_MODE_VOLUME)
		{
			ListBase depth_peels;
			DepthPeel *p1, *p2;
			float *last_p = NULL;
			float dist = FLT_MAX;
			float p[3];
			short mval[2];
	
			getmouseco_areawin(mval);
			
			depth_peels.first = depth_peels.last = NULL;
			
			peelObjects(&depth_peels, mval);
			
//			if (stk->nb_points > 0 && stk->points[stk->nb_points - 1].type == PT_CONTINUOUS)
//			{
//				last_p = stk->points[stk->nb_points - 1].p;
//			}
//			else if (LAST_SNAP_POINT_VALID)
//			{
//				last_p = LAST_SNAP_POINT;
//			}
			
			
			for (p1 = depth_peels.first; p1; p1 = p1->next)
			{
				if (p1->flag == 0)
				{
					float vec[3];
					float new_dist;
					
					p2 = NULL;
					p1->flag = 1;
		
					/* if peeling objects, take the first and last from each object */			
					if (G.scene->snap_flag & SCE_SNAP_PEEL_OBJECT)
					{
						DepthPeel *peel;
						for (peel = p1->next; peel; peel = peel->next)
						{
							if (peel->ob == p1->ob)
							{
								peel->flag = 1;
								p2 = peel;
							}
						}
					}
					/* otherwise, pair first with second and so on */
					else
					{
						for (p2 = p1->next; p2 && p2->ob != p1->ob; p2 = p2->next)
						{
							/* nothing to do here */
						}
					}
					
					if (p2)
					{
						p2->flag = 1;
						
						VecAddf(vec, p1->p, p2->p);
						VecMulf(vec, 0.5f);
					}
					else
					{
						VECCOPY(vec, p1->p);
					}
					
					if (last_p == NULL)
					{
						VECCOPY(p, vec);
						dist = 0;
						break;
					}
					
					new_dist = VecLenf(last_p, vec);
					
					if (new_dist < dist)
					{
						VECCOPY(p, vec);
						dist = new_dist;
					}
				}
			}
			
			if (dist != FLT_MAX)
			{
				VECCOPY(loc, p);
				found = 1;
			}
			
			BLI_freelistN(&depth_peels);
		}
		else
		{
			if (G.obedit == NULL)
			{
				mode = NOT_SELECTED;
			}
			else
			{
				mode = NOT_ACTIVE;
			}
				
			found = snapObjects(&dist, loc, no, NOT_SELECTED);
		}
		
		if (found == 1)
		{
			float tangent[3];
			
			VecSubf(tangent, loc, t->tsnap.snapPoint);
			tangent[2] = 0; 
			
			if (Inpf(tangent, tangent) > 0)
			{
				VECCOPY(t->tsnap.snapTangent, tangent);
			}
			
			VECCOPY(t->tsnap.snapPoint, loc);
			VECCOPY(t->tsnap.snapNormal, no);

			t->tsnap.status |=  POINT_INIT;
		}
		else
		{
			t->tsnap.status &= ~POINT_INIT;
		}
	}
	else if (t->spacetype == SPACE_IMAGE && G.obedit != NULL && G.obedit->type==OB_MESH)
	{	/* same as above but for UV's */
		MTFace *nearesttf=NULL;
		float aspx, aspy;
		int face_corner;
		
		find_nearest_uv(&nearesttf, NULL, NULL, &face_corner);

		if (nearesttf != NULL)
		{
			VECCOPY2D(t->tsnap.snapPoint, nearesttf->uv[face_corner]);

			transform_aspect_ratio_tface_uv(&aspx, &aspy);
			t->tsnap.snapPoint[0] *= aspx;
			t->tsnap.snapPoint[1] *= aspy;

			//Mat4MulVecfl(G.obedit->obmat, t->tsnap.snapPoint);
			
			t->tsnap.status |=  POINT_INIT;
		}
		else
		{
			t->tsnap.status &= ~POINT_INIT;
		}
	}
}

/********************** TARGET **************************/

void TargetSnapCenter(TransInfo *t)
{
	// Only need to calculate once
	if ((t->tsnap.status & TARGET_INIT) == 0)
	{
		VECCOPY(t->tsnap.snapTarget, t->center);	
		if(t->flag & (T_EDIT|T_POSE)) {
			Object *ob= G.obedit?G.obedit:t->poseobj;
			Mat4MulVecfl(ob->obmat, t->tsnap.snapTarget);
		}
		
		t->tsnap.status |= TARGET_INIT;		
	}
}

void TargetSnapActive(TransInfo *t)
{
	// Only need to calculate once
	if ((t->tsnap.status & TARGET_INIT) == 0)
	{
		TransData *td = NULL;
		TransData *active_td = NULL;
		int i;

		for(td = t->data, i = 0 ; i < t->total && td->flag & TD_SELECTED ; i++, td++)
		{
			if (td->flag & TD_ACTIVE)
			{
				active_td = td;
				break;
			}
		}

		if (active_td)
		{	
			VECCOPY(t->tsnap.snapTarget, active_td->center);
				
			if(t->flag & (T_EDIT|T_POSE)) {
				Object *ob= G.obedit?G.obedit:t->poseobj;
				Mat4MulVecfl(ob->obmat, t->tsnap.snapTarget);
			}
			
			t->tsnap.status |= TARGET_INIT;
		}
		/* No active, default to median */
		else
		{
			t->tsnap.modeTarget = SNAP_MEDIAN;
			t->tsnap.targetSnap = TargetSnapMedian;
			TargetSnapMedian(t);
		}		
	}
}

void TargetSnapMedian(TransInfo *t)
{
	// Only need to calculate once
	if ((t->tsnap.status & TARGET_INIT) == 0)
	{
		TransData *td = NULL;
		int i;

		t->tsnap.snapTarget[0] = 0;
		t->tsnap.snapTarget[1] = 0;
		t->tsnap.snapTarget[2] = 0;
		
		for(td = t->data, i = 0 ; i < t->total && td->flag & TD_SELECTED ; i++, td++)
		{
			VecAddf(t->tsnap.snapTarget, t->tsnap.snapTarget, td->center);
		}
		
		VecMulf(t->tsnap.snapTarget, 1.0 / t->total);
		
		if(t->flag & (T_EDIT|T_POSE)) {
			Object *ob= G.obedit?G.obedit:t->poseobj;
			Mat4MulVecfl(ob->obmat, t->tsnap.snapTarget);
		}
		
		t->tsnap.status |= TARGET_INIT;		
	}
}

void TargetSnapClosest(TransInfo *t)
{
	// Only valid if a snap point has been selected
	if (t->tsnap.status & POINT_INIT)
	{
		TransData *closest = NULL, *td = NULL;
		
		/* Object mode */
		if (t->flag & T_OBJECT)
		{
			int i;
			for(td = t->data, i = 0 ; i < t->total && td->flag & TD_SELECTED ; i++, td++)
			{
				struct BoundBox *bb = object_get_boundbox(td->ob);
				
				/* use boundbox if possible */
				if (bb)
				{
					int j;
					
					for (j = 0; j < 8; j++) {
						float loc[3];
						float dist;
						
						VECCOPY(loc, bb->vec[j]);
						Mat4MulVecfl(td->ext->obmat, loc);
						
						dist = t->tsnap.distance(t, loc, t->tsnap.snapPoint);
						
						if (closest == NULL || fabs(dist) < fabs(t->tsnap.dist))
						{
							VECCOPY(t->tsnap.snapTarget, loc);
							closest = td;
							t->tsnap.dist = dist; 
						}
					}
				}
				/* use element center otherwise */
				else
				{
					float loc[3];
					float dist;
					
					VECCOPY(loc, td->center);
					
					dist = t->tsnap.distance(t, loc, t->tsnap.snapPoint);
					
					if (closest == NULL || fabs(dist) < fabs(t->tsnap.dist))
					{
						VECCOPY(t->tsnap.snapTarget, loc);
						closest = td;
						t->tsnap.dist = dist; 
					}
				}
			}
		}
		else
		{
			int i;
			for(td = t->data, i = 0 ; i < t->total && td->flag & TD_SELECTED ; i++, td++)
			{
				float loc[3];
				float dist;
				
				VECCOPY(loc, td->center);
				
				if(t->flag & (T_EDIT|T_POSE)) {
					Object *ob= G.obedit?G.obedit:t->poseobj;
					Mat4MulVecfl(ob->obmat, loc);
				}
				
				dist = t->tsnap.distance(t, loc, t->tsnap.snapPoint);
				
				if (closest == NULL || fabs(dist) < fabs(t->tsnap.dist))
				{
					VECCOPY(t->tsnap.snapTarget, loc);
					closest = td;
					t->tsnap.dist = dist; 
				}
			}
		}
		
		t->tsnap.status |= TARGET_INIT;
	}
}
/*================================================================*/

int snapFace(float v1co[3], float v2co[3], float v3co[3], float *v4co, short mval[2], float ray_start[3], float ray_start_local[3], float ray_normal_local[3], float obmat[][4], float timat[][3], float *loc, float *no, int *dist, float *depth)
{
	float lambda;
	int result;
	int retval = 0;
	
	result = RayIntersectsTriangleThreshold(ray_start_local, ray_normal_local, v1co, v2co, v3co, &lambda, NULL, 0.001);
	
	if (result) {
		float location[3], normal[3];
		float intersect[3];
		float new_depth;
		int screen_loc[2];
		int new_dist;
		
		VECCOPY(intersect, ray_normal_local);
		VecMulf(intersect, lambda);
		VecAddf(intersect, intersect, ray_start_local);
		
		VECCOPY(location, intersect);
		
		if (v4co)
			CalcNormFloat4(v1co, v2co, v3co, v4co, normal);
		else
			CalcNormFloat(v1co, v2co, v3co, normal);

		Mat4MulVecfl(obmat, location);
		
		new_depth = VecLenf(location, ray_start);					
		
		project_int(location, screen_loc);
		new_dist = abs(screen_loc[0] - mval[0]) + abs(screen_loc[1] - mval[1]);
		
		if (new_dist <= *dist && new_depth < *depth) 
		{
			*depth = new_depth;
			retval = 1;
			
			VECCOPY(loc, location);
			VECCOPY(no, normal);
			
			Mat3MulVecfl(timat, no);
			Normalize(no);

			*dist = new_dist;
		} 
	}
	
	return retval;
}

int snapEdge(float v1co[3], short v1no[3], float v2co[3], short v2no[3], short mval[2], float ray_start[3], float ray_start_local[3], float ray_normal_local[3], float obmat[][4], float timat[][3], float *loc, float *no, int *dist, float *depth)
{
	float intersect[3] = {0, 0, 0}, ray_end[3], dvec[3];
	int result;
	int retval = 0;
	
	VECCOPY(ray_end, ray_normal_local);
	VecMulf(ray_end, 2000);
	VecAddf(ray_end, ray_start_local, ray_end);
	
	result = LineIntersectLine(v1co, v2co, ray_start_local, ray_end, intersect, dvec); /* dvec used but we don't care about result */
	
	if (result)
	{
		float edge_loc[3], vec[3];
		float mul;
	
		/* check for behind ray_start */
		VecSubf(dvec, intersect, ray_start_local);
		
		VecSubf(edge_loc, v1co, v2co);
		VecSubf(vec, intersect, v2co);
		
		mul = Inpf(vec, edge_loc) / Inpf(edge_loc, edge_loc);
		
		if (mul > 1) {
			mul = 1;
			VECCOPY(intersect, v1co);
		}
		else if (mul < 0) {
			mul = 0;
			VECCOPY(intersect, v2co);
		}

		if (Inpf(ray_normal_local, dvec) > 0)
		{
			float location[3];
			float new_depth;
			int screen_loc[2];
			int new_dist;
			
			VECCOPY(location, intersect);
			
			Mat4MulVecfl(obmat, location);
			
			new_depth = VecLenf(location, ray_start);					
			
			project_int(location, screen_loc);
			new_dist = abs(screen_loc[0] - mval[0]) + abs(screen_loc[1] - mval[1]);
			
			/* 10% threshold if edge is closer but a bit further
			 * this takes care of series of connected edges a bit slanted w.r.t the viewport
			 * otherwise, it would stick to the verts of the closest edge and not slide along merrily 
			 * */
			if (new_dist <= *dist && new_depth < *depth * 1.01)
			{
				float n1[3], n2[3];
				
				*depth = new_depth;
				retval = 1;
				
				VecSubf(edge_loc, v1co, v2co);
				VecSubf(vec, intersect, v2co);
				
				mul = Inpf(vec, edge_loc) / Inpf(edge_loc, edge_loc);
				
				if (no)
				{
					NormalShortToFloat(n1, v1no);						
					NormalShortToFloat(n2, v2no);
					VecLerpf(no, n2, n1, mul);
					Mat3MulVecfl(timat, no);
					Normalize(no);
				}			

				VECCOPY(loc, location);
				
				*dist = new_dist;
			} 
		}
	}
	
	return retval;
}

int snapVertex(float vco[3], short vno[3], short mval[2], float ray_start[3], float ray_start_local[3], float ray_normal_local[3], float obmat[][4], float timat[][3], float *loc, float *no, int *dist, float *depth)
{
	int retval = 0;
	float dvec[3];
	
	VecSubf(dvec, vco, ray_start_local);
	
	if (Inpf(ray_normal_local, dvec) > 0)
	{
		float location[3];
		float new_depth;
		int screen_loc[2];
		int new_dist;
		
		VECCOPY(location, vco);
		
		Mat4MulVecfl(obmat, location);
		
		new_depth = VecLenf(location, ray_start);					
		
		project_int(location, screen_loc);
		new_dist = abs(screen_loc[0] - mval[0]) + abs(screen_loc[1] - mval[1]);
		
		if (new_dist <= *dist && new_depth < *depth)
		{
			*depth = new_depth;
			retval = 1;
			
			VECCOPY(loc, location);
			
			if (no)
			{
				NormalShortToFloat(no, vno);
				Mat3MulVecfl(timat, no);
				Normalize(no);
			}

			*dist = new_dist;
		} 
	}
	
	return retval;
}

int snapArmature(Object *ob, bArmature *ar, float obmat[][4], float ray_start[3], float ray_normal[3], short mval[2], float *loc, float *no, int *dist, float *depth)
{
	Bone *b = ar->bonebase.first;
	float imat[4][4];
	float ray_start_local[3], ray_normal_local[3];
	int retval = 0;

	Mat4Invert(imat, obmat);

	VECCOPY(ray_start_local, ray_start);
	VECCOPY(ray_normal_local, ray_normal);
	
	Mat4MulVecfl(imat, ray_start_local);
	Mat4Mul3Vecfl(imat, ray_normal_local);
			
	while(b)
	{
		switch (G.scene->snap_mode)
		{
			case SCE_SNAP_MODE_VERTEX:
				retval |= snapVertex(b->arm_head, NULL, mval, ray_start, ray_start_local, ray_normal_local, obmat, NULL, loc, NULL, dist, depth);
				retval |= snapVertex(b->arm_tail, NULL, mval, ray_start, ray_start_local, ray_normal_local, obmat, NULL, loc, NULL, dist, depth);
				break;
			case SCE_SNAP_MODE_EDGE:
				retval |= snapEdge(b->arm_head, NULL, b->arm_tail, NULL, mval, ray_start, ray_start_local, ray_normal_local, obmat, NULL, loc, NULL, dist, depth);
				break;
		}
		
		
		if (b->childbase.first != NULL)
		{
			b = b->childbase.first;
		}
		else
		{
			while(1)
			{
				if (b->next != NULL)
				{
					b = b->next;
					break;
				}
				else if (b->parent != NULL)
				{
					b = b->parent;
				}
				else /* nothing to go to */
				{
					b = NULL;
					break;
				}
			}
		}
	}

	return retval;
}

int snapDerivedMesh(Object *ob, DerivedMesh *dm, float obmat[][4], float ray_start[3], float ray_normal[3], short mval[2], float *loc, float *no, int *dist, float *depth, short EditMesh)
{
	int retval = 0;
	int totvert = dm->getNumVerts(dm);
	int totface = dm->getNumFaces(dm);
	
	if (totvert > 0) {
		float imat[4][4];
		float timat[3][3]; /* transpose inverse matrix for normals */
		float ray_start_local[3], ray_normal_local[3];
		int test = 1;

		Mat4Invert(imat, obmat);

		Mat3CpyMat4(timat, imat);
		Mat3Transp(timat);
		
		VECCOPY(ray_start_local, ray_start);
		VECCOPY(ray_normal_local, ray_normal);
		
		Mat4MulVecfl(imat, ray_start_local);
		Mat4Mul3Vecfl(imat, ray_normal_local);
		
		
		/* If number of vert is more than an arbitrary limit, 
		 * test against boundbox first
		 * */
		if (totface > 16) {
			struct BoundBox *bb = object_get_boundbox(ob);
			test = ray_hit_boundbox(bb, ray_start_local, ray_normal_local);
		}
		
		if (test == 1) {
			
			switch (G.scene->snap_mode)
			{
				case SCE_SNAP_MODE_FACE:
				{ 
					MVert *verts = dm->getVertArray(dm);
					MFace *faces = dm->getFaceArray(dm);
					int *index_array = NULL;
					int index = 0;
					int i;
					
					if (EditMesh)
					{
						index_array = dm->getFaceDataArray(dm, CD_ORIGINDEX);
						EM_init_index_arrays(0, 0, 1);
					}
					
					for( i = 0; i < totface; i++) {
						EditFace *efa = NULL;
						MFace *f = faces + i;
						
						test = 1; /* reset for every face */
					
						if (EditMesh)
						{
							if (index_array)
							{
								index = index_array[i];
							}
							else
							{
								index = i;
							}
							
							if (index == ORIGINDEX_NONE)
							{
								test = 0;
							}
							else
							{
								efa = EM_get_face_for_index(index);
								
								if (efa && (efa->h || (efa->v1->f & SELECT) || (efa->v2->f & SELECT) || (efa->v3->f & SELECT) || (efa->v4 && efa->v4->f & SELECT)))
								{
									test = 0;
								}
							}
						}
						
						
						if (test)
						{
							int result;
							float *v4co = NULL;
							
							if (f->v4)
							{
								v4co = verts[f->v4].co;
							}
							
							result = snapFace(verts[f->v1].co, verts[f->v2].co, verts[f->v3].co, v4co, mval, ray_start, ray_start_local, ray_normal_local, obmat, timat, loc, no, dist, depth);
							retval |= result;

							if (f->v4 && result == 0)
							{
								retval |= snapFace(verts[f->v3].co, verts[f->v4].co, verts[f->v1].co, verts[f->v2].co, mval, ray_start, ray_start_local, ray_normal_local, obmat, timat, loc, no, dist, depth);
							}
						}
					}
					
					if (EditMesh)
					{
						EM_free_index_arrays();
					}
					break;
				}
				case SCE_SNAP_MODE_VERTEX:
				{
					MVert *verts = dm->getVertArray(dm);
					int *index_array = NULL;
					int index = 0;
					int i;
					
					if (EditMesh)
					{
						index_array = dm->getVertDataArray(dm, CD_ORIGINDEX);
						EM_init_index_arrays(1, 0, 0);
					}
					
					for( i = 0; i < totvert; i++) {
						EditVert *eve = NULL;
						MVert *v = verts + i;
						
						test = 1; /* reset for every vert */
					
						if (EditMesh)
						{
							if (index_array)
							{
								index = index_array[i];
							}
							else
							{
								index = i;
							}
							
							if (index == ORIGINDEX_NONE)
							{
								test = 0;
							}
							else
							{
								eve = EM_get_vert_for_index(index);
								
								if (eve && (eve->h || (eve->f & SELECT)))
								{
									test = 0;
								}
							}
						}
						
						
						if (test)
						{
							retval |= snapVertex(v->co, v->no, mval, ray_start, ray_start_local, ray_normal_local, obmat, timat, loc, no, dist, depth);
						}
					}

					if (EditMesh)
					{
						EM_free_index_arrays();
					}
					break;
				}
				case SCE_SNAP_MODE_EDGE:
				{
					MVert *verts = dm->getVertArray(dm);
					MEdge *edges = dm->getEdgeArray(dm);
					int totedge = dm->getNumEdges(dm);
					int *index_array = NULL;
					int index = 0;
					int i;
					
					if (EditMesh)
					{
						index_array = dm->getEdgeDataArray(dm, CD_ORIGINDEX);
						EM_init_index_arrays(0, 1, 0);
					}
					
					for( i = 0; i < totedge; i++) {
						EditEdge *eed = NULL;
						MEdge *e = edges + i;
						
						test = 1; /* reset for every vert */
					
						if (EditMesh)
						{
							if (index_array)
							{
								index = index_array[i];
							}
							else
							{
								index = i;
							}
							
							if (index == ORIGINDEX_NONE)
							{
								test = 0;
							}
							else
							{
								eed = EM_get_edge_for_index(index);
								
								if (eed && (eed->h || (eed->v1->f & SELECT) || (eed->v2->f & SELECT)))
								{
									test = 0;
								}
							}
						}
						
						
						if (test)
						{
							retval |= snapEdge(verts[e->v1].co, verts[e->v1].no, verts[e->v2].co, verts[e->v2].no, mval, ray_start, ray_start_local, ray_normal_local, obmat, timat, loc, no, dist, depth);
						}
					}

					if (EditMesh)
					{
						EM_free_index_arrays();
					}
					break;
				}
			}
		}
	}

	return retval;
} 

int snapObjects(int *dist, float *loc, float *no, SnapMode mode) {
	Base *base;
	float depth = FLT_MAX;
	int retval = 0;
	short mval[2];
	float ray_start[3], ray_normal[3];
	
	getmouseco_areawin(mval);
	viewray(mval, ray_start, ray_normal);

	if (mode == NOT_ACTIVE)
	{
		DerivedMesh *dm;
		Object *ob = G.obedit;
		
		if (ob->type == OB_MESH)
		{
			dm = editmesh_get_derived_cage(CD_MASK_BAREMESH);
			
			retval = snapDerivedMesh(ob, dm, ob->obmat, ray_start, ray_normal, mval, loc, no, dist, &depth, 1);
			
			dm->release(dm);
		}
	}
	
	base= FIRSTBASE;
	for ( base = FIRSTBASE; base != NULL; base = base->next ) {
		if ( BASE_SELECTABLE(base) && (base->flag & (BA_HAS_RECALC_OB|BA_HAS_RECALC_DATA)) == 0 && ((mode == NOT_SELECTED && (base->flag & (SELECT|BA_WAS_SEL)) == 0) || (mode == NOT_ACTIVE && base != BASACT)) ) {
			Object *ob = base->object;
			
			if (ob->transflag & OB_DUPLI)
			{
				DupliObject *dupli_ob;
				ListBase *lb = object_duplilist(G.scene, ob);
				
				for(dupli_ob = lb->first; dupli_ob; dupli_ob = dupli_ob->next)
				{
					Object *ob = dupli_ob->ob;
					
					if (ob->type == OB_MESH) {
						DerivedMesh *dm;
						int editmesh = 0;
						int val;
						
						if (ob == G.obedit)
						{
							dm = editmesh_get_derived_cage(CD_MASK_BAREMESH);
							editmesh = 1;
						}
						else
						{
							dm = mesh_get_derived_final(ob, CD_MASK_BAREMESH);
						}
						
						val = snapDerivedMesh(ob, dm, dupli_ob->mat, ray_start, ray_normal, mval, loc, no, dist, &depth, editmesh);
	
						retval = retval || val;
	
						dm->release(dm);
					}
				}
				
				free_object_duplilist(lb);
			}
			
			if (ob->type == OB_MESH) {
				DerivedMesh *dm = mesh_get_derived_final(ob, CD_MASK_BAREMESH);
				int val;
				
				val = snapDerivedMesh(ob, dm, ob->obmat, ray_start, ray_normal, mval, loc, no, dist, &depth, 0);
				
				retval = retval || val;
				
				dm->release(dm);
			}
			else if (ob->type == OB_ARMATURE)
			{
				int val;
				
				val = snapArmature(ob, ob->data, ob->obmat, ray_start, ray_normal, mval, loc, no, dist, &depth);
				
				retval = retval || val;
			}
		}
	}
	
	return retval;
}

/******************** PEELING *********************************/


int cmpPeel(void *arg1, void *arg2)
{
	DepthPeel *p1 = arg1;
	DepthPeel *p2 = arg2;
	int val = 0;
	
	if (p1->depth < p2->depth)
	{
		val = -1;
	}
	else if (p1->depth > p2->depth)
	{
		val = 1;
	}
	
	return val;
}

void removeDoublesPeel(ListBase *depth_peels)
{
	DepthPeel *peel;
	
	for (peel = depth_peels->first; peel; peel = peel->next)
	{
		DepthPeel *next_peel = peel->next;
		
		if (peel && next_peel && ABS(peel->depth - next_peel->depth) < 0.0015)
		{
			peel->next = next_peel->next;
			
			if (next_peel->next)
			{
				next_peel->next->prev = peel;
			}
			
			MEM_freeN(next_peel);
		}
	}
}

void addDepthPeel(ListBase *depth_peels, float depth, float p[3], float no[3], Object *ob)
{
	DepthPeel *peel = MEM_callocN(sizeof(DepthPeel), "DepthPeel");
	
	peel->depth = depth;
	peel->ob = ob;
	VECCOPY(peel->p, p);
	VECCOPY(peel->no, no);
	
	BLI_addtail(depth_peels, peel);
	
	peel->flag = 0;
}

int peelDerivedMesh(Object *ob, DerivedMesh *dm, float obmat[][4], float ray_start[3], float ray_normal[3], short mval[2], ListBase *depth_peels)
{
	int retval = 0;
	int totvert = dm->getNumVerts(dm);
	int totface = dm->getNumFaces(dm);
	
	if (totvert > 0) {
		float imat[4][4];
		float timat[3][3]; /* transpose inverse matrix for normals */
		float ray_start_local[3], ray_normal_local[3];
		int test = 1;

		Mat4Invert(imat, obmat);

		Mat3CpyMat4(timat, imat);
		Mat3Transp(timat);
		
		VECCOPY(ray_start_local, ray_start);
		VECCOPY(ray_normal_local, ray_normal);
		
		Mat4MulVecfl(imat, ray_start_local);
		Mat4Mul3Vecfl(imat, ray_normal_local);
		
		
		/* If number of vert is more than an arbitrary limit, 
		 * test against boundbox first
		 * */
		if (totface > 16) {
			struct BoundBox *bb = object_get_boundbox(ob);
			test = ray_hit_boundbox(bb, ray_start_local, ray_normal_local);
		}
		
		if (test == 1) {
			MVert *verts = dm->getVertArray(dm);
			MFace *faces = dm->getFaceArray(dm);
			int i;
			
			for( i = 0; i < totface; i++) {
				MFace *f = faces + i;
				float lambda;
				int result;
				
				
				result = RayIntersectsTriangleThreshold(ray_start_local, ray_normal_local, verts[f->v1].co, verts[f->v2].co, verts[f->v3].co, &lambda, NULL, 0.001);
				
				if (result) {
					float location[3], normal[3];
					float intersect[3];
					float new_depth;
					
					VECCOPY(intersect, ray_normal_local);
					VecMulf(intersect, lambda);
					VecAddf(intersect, intersect, ray_start_local);
					
					VECCOPY(location, intersect);
					
					if (f->v4)
						CalcNormFloat4(verts[f->v1].co, verts[f->v2].co, verts[f->v3].co, verts[f->v4].co, normal);
					else
						CalcNormFloat(verts[f->v1].co, verts[f->v2].co, verts[f->v3].co, normal);

					Mat4MulVecfl(obmat, location);
					
					new_depth = VecLenf(location, ray_start);					
					
					Mat3MulVecfl(timat, normal);
					Normalize(normal);

					addDepthPeel(depth_peels, new_depth, location, normal, ob);
				}
		
				if (f->v4 && result == 0)
				{
					result = RayIntersectsTriangleThreshold(ray_start_local, ray_normal_local, verts[f->v3].co, verts[f->v4].co, verts[f->v1].co, &lambda, NULL, 0.001);
					
					if (result) {
						float location[3], normal[3];
						float intersect[3];
						float new_depth;
						
						VECCOPY(intersect, ray_normal_local);
						VecMulf(intersect, lambda);
						VecAddf(intersect, intersect, ray_start_local);
						
						VECCOPY(location, intersect);
						
						if (f->v4)
							CalcNormFloat4(verts[f->v1].co, verts[f->v2].co, verts[f->v3].co, verts[f->v4].co, normal);
						else
							CalcNormFloat(verts[f->v1].co, verts[f->v2].co, verts[f->v3].co, normal);

						Mat4MulVecfl(obmat, location);
						
						new_depth = VecLenf(location, ray_start);					
						
						Mat3MulVecfl(timat, normal);
						Normalize(normal);
	
						addDepthPeel(depth_peels, new_depth, location, normal, ob);
					} 
				}
			}
		}
	}

	return retval;
} 

int peelObjects(ListBase *depth_peels, short mval[2])
{
	Base *base;
	int retval = 0;
	float ray_start[3], ray_normal[3];
	
	viewray(mval, ray_start, ray_normal);

	base= FIRSTBASE;
	for ( base = FIRSTBASE; base != NULL; base = base->next ) {
		if ( BASE_SELECTABLE(base) ) {
			Object *ob = base->object;
			
			if (ob->transflag & OB_DUPLI)
			{
				DupliObject *dupli_ob;
				ListBase *lb = object_duplilist(G.scene, ob);
				
				for(dupli_ob = lb->first; dupli_ob; dupli_ob = dupli_ob->next)
				{
					Object *ob = dupli_ob->ob;
					
					if (ob->type == OB_MESH) {
						DerivedMesh *dm = mesh_get_derived_final(ob, CD_MASK_BAREMESH);
						int val;
						
						val = peelDerivedMesh(ob, dm, dupli_ob->mat, ray_start, ray_normal, mval, depth_peels);
	
						retval = retval || val;
	
						dm->release(dm);
					}
				}
				
				free_object_duplilist(lb);
			}
			
			if (ob->type == OB_MESH) {
				DerivedMesh *dm = NULL;
				int val;

				if (ob != G.obedit)
				{
					dm = mesh_get_derived_final(ob, CD_MASK_BAREMESH);
					
					val = peelDerivedMesh(ob, dm, ob->obmat, ray_start, ray_normal, mval, depth_peels);
				}
				else
				{
					dm = editmesh_get_derived_cage(CD_MASK_BAREMESH);
					
					val = peelDerivedMesh(ob, dm, ob->obmat, ray_start, ray_normal, mval, depth_peels);
				}
					
				retval = retval || val;
				
				dm->release(dm);
			}
		}
	}
	
	BLI_sortlist(depth_peels, cmpPeel);
	removeDoublesPeel(depth_peels);
	
	return retval;
}

/*================================================================*/

static void applyGrid(TransInfo *t, float *val, int max_index, float fac[3], GearsType action);


void snapGridAction(TransInfo *t, float *val, GearsType action) {
	float fac[3];

	fac[NO_GEARS]    = t->snap[0];
	fac[BIG_GEARS]   = t->snap[1];
	fac[SMALL_GEARS] = t->snap[2];
	
	applyGrid(t, val, t->idx_max, fac, action);
}


void snapGrid(TransInfo *t, float *val) {
	int invert;
	GearsType action;

	// Only do something if using Snap to Grid
	if (t->tsnap.modePoint != SNAP_GRID)
		return;

	if(t->mode==TFM_ROTATION || t->mode==TFM_WARP || t->mode==TFM_TILT || t->mode==TFM_TRACKBALL || t->mode==TFM_BONE_ROLL)
		invert = U.flag & USER_AUTOROTGRID;
	else if(t->mode==TFM_RESIZE || t->mode==TFM_SHEAR || t->mode==TFM_BONESIZE || t->mode==TFM_SHRINKFATTEN || t->mode==TFM_CURVE_SHRINKFATTEN)
		invert = U.flag & USER_AUTOSIZEGRID;
	else
		invert = U.flag & USER_AUTOGRABGRID;

	if(invert) {
		action = (G.qual & LR_CTRLKEY) ? NO_GEARS: BIG_GEARS;
	}
	else {
		action = (G.qual & LR_CTRLKEY) ? BIG_GEARS : NO_GEARS;
	}
	
	if (action == BIG_GEARS && (G.qual & LR_SHIFTKEY)) {
		action = SMALL_GEARS;
	}

	snapGridAction(t, val, action);
}


static void applyGrid(TransInfo *t, float *val, int max_index, float fac[3], GearsType action)
{
	int i;
	float asp[3] = {1.0f, 1.0f, 1.0f}; // TODO: Remove hard coded limit here (3)

	// Early bailing out if no need to snap
	if (fac[action] == 0.0)
		return;
	
	/* evil hack - snapping needs to be adapted for image aspect ratio */
	if((t->spacetype==SPACE_IMAGE) && (t->mode==TFM_TRANSLATION)) {
		transform_aspect_ratio_tface_uv(asp, asp+1);
	}

	for (i=0; i<=max_index; i++) {
		val[i]= fac[action]*asp[i]*(float)floor(val[i]/(fac[action]*asp[i]) +.5);
	}
}