topviewfuncs.c

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/*************************************************************************
 * Copyright (c) 2011 AT&T Intellectual Property 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: Details at https://graphviz.org
 *************************************************************************/
 
#include <assert.h>
#include "topviewfuncs.h"
#include <cgraph/cgraph.h>
#include "smyrna_utils.h"
#include <common/colorprocs.h>
#include "draw.h"
#include "frmobjectui.h"
#include <xdot/xdot.h>
#include <glcomp/glutils.h>
#include "selectionfuncs.h"
#include <common/types.h>
#include <common/utils.h>
#include <limits.h>
#include <float.h>
#include <math.h>
#include <stdbool.h>
#include <stdlib.h>
#include <util/alloc.h>
#include <util/gv_ctype.h>
 
static xdot *parseXdotwithattrs(void *e)
{
    xdot* xDot=NULL;
    xDot=parseXDotFOn (agget(e,"_draw_" ), OpFns,sizeof(sdot_op), xDot);
    if (agobjkind(e) == AGRAPH)
        xDot=parseXDotFOn (agget(e,"_background" ), OpFns,sizeof(sdot_op), xDot);
    xDot=parseXDotFOn (agget(e,"_ldraw_" ), OpFns,sizeof(sdot_op), xDot);
    xDot=parseXDotFOn (agget(e,"_hdraw_" ), OpFns,sizeof(sdot_op), xDot);
    xDot=parseXDotFOn (agget(e,"_tdraw_" ), OpFns,sizeof(sdot_op), xDot);
    xDot=parseXDotFOn (agget(e,"_hldraw_" ), OpFns,sizeof(sdot_op), xDot);
    xDot=parseXDotFOn (agget(e,"_tldraw_" ), OpFns,sizeof(sdot_op), xDot);
    if(xDot)
    {
        for (size_t cnt = 0; cnt < xDot->cnt; cnt++)
        {
            ((sdot_op*)(xDot->ops))[cnt].obj=e;
        }
    }
    return xDot;
 
}
 
static void set_boundaries(Agraph_t * g)
{
    Agnode_t *v;
    Agsym_t* pos_attr = GN_pos(g);
    glCompPoint pos;
    float left = FLT_MAX, right = -FLT_MAX, top = -FLT_MAX, bottom = FLT_MAX;
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        pos=getPointFromStr(agxget(v, pos_attr));
 
        left = fminf(left, pos.x);
        right = fmaxf(right, pos.x);
        top = fmaxf(top, pos.y);
        bottom = fminf(bottom, pos.y);
    }
    view->bdxLeft = left;
    view->bdyTop = top;
    view->bdxRight = right;
    view->bdyBottom = bottom;
}
 
static void draw_xdot(xdot* x, double base_z)
{
        sdot_op *op;
        if (!x)
                return;
 
        view->Topview->global_z=base_z;
 
        op=(sdot_op*)x->ops;
        for (size_t i = 0; i < x->cnt; i++, op++)
        {
                if(op->op.drawfunc)
                        op->op.drawfunc(&op->op,0);
        }
 
 
}
 
 
 
static glCompPoint getEdgeHead(Agedge_t * edge)
{   
    return getPointFromStr(agget(aghead(edge),"pos"));
}
static glCompPoint getEdgeTail(Agedge_t *  edge)
{
    return getPointFromStr(agget(agtail(edge),"pos"));
}
 
static float getEdgeLength(Agedge_t *edge) {
    glCompPoint A,B;
    A=getEdgeTail(edge);
    B=getEdgeHead(edge);
    float rv = (A.x - B.x) * (A.x - B.x) + (A.y - B.y) * (A.y - B.y) + (A.z - B.z) * (A.z - B.z);
    rv=sqrtf(rv);
    return rv;
}
 
static void glCompColorxlate(glCompColor *c, const char *str) {
        gvcolor_t cl;
        colorxlate(str, &cl, RGBA_DOUBLE);
        c->R=cl.u.RGBA[0];
        c->G=cl.u.RGBA[1];
        c->B=cl.u.RGBA[2];
        c->A=cl.u.RGBA[3];
}
 
/* If the "visible" attribute is not set or "", return true
 * else evaluate as boolean
 */
static int visible(Agsym_t* attr, void* obj)
{
    if (attr) {
        const char *const s = agxget(obj, attr);
        if (*s) return mapbool(s);
    }
    return 1;
}
 
static int object_color(void* obj,glCompColor* c)
{
    gvcolor_t cl;
    Agraph_t* g=view->g[view->activeGraph];
    Agraph_t* objg=agraphof(obj);
    float Alpha = 1;
    Agsym_t* vis;
 
    const int objType = AGTYPE(obj);
 
    if(objType==AGEDGE) {
        Alpha=getAttrFloat(g,objg,"defaultedgealpha",1);
        vis = GE_visible (objg);
    }
    else {
        assert(objType == AGNODE);
        Alpha=getAttrFloat(g,objg,"defaultnodealpha",1);
        vis = GN_visible (objg);
    }
    if (!visible(vis,obj))
        return 0;
 
    char *previous_color_scheme = setColorScheme(agget (obj, "colorscheme"));
    /*get objects's color attribute */
    const char *const bf = getAttrStr(g,obj,"color",NULL);
    if(bf && (*bf)) {
        colorxlate(bf, &cl, RGBA_DOUBLE);
        c->R = cl.u.RGBA[0];
        c->G = cl.u.RGBA[1];
        c->B = cl.u.RGBA[2];
        c->A = cl.u.RGBA[3]*Alpha;
    }
    else
    {
        if(objType==AGEDGE)
            getcolorfromschema(view->colschms, getEdgeLength(obj), view->Topview->maxedgelen,c);
        else
        {
            colorxlate(agget(g, "defaultnodecolor"),&cl, RGBA_DOUBLE);
                c->R = cl.u.RGBA[0];
            c->G = cl.u.RGBA[1];
            c->B = cl.u.RGBA[2];
            c->A = cl.u.RGBA[3];
        }
        c->A *= Alpha;
 
    }
 
    char *color_scheme = setColorScheme(previous_color_scheme);
    free(color_scheme);
    free(previous_color_scheme);
 
    return 1;
}
 
 
/*
        draws multi edges , single edges
        this function assumes     glBegin(GL_LINES) has been called 
*/
static void draw_edge(glCompPoint posT, glCompPoint posH) {
    glVertex3f(posT.x, posT.y, posT.z);
    glVertex3f(posH.x, posH.y, posH.z);
}
 
static char* labelOf (Agraph_t* g, Agnode_t* v)
{
    char* lbl;
    char* s;
 
    Agsym_t* data_attr = GN_labelattribute(g);
    if (data_attr)
        s = agxget (v, data_attr);
    else
        s = agxget (g, GG_labelattribute(g));
    if ((*s == '\0') || !strcmp (s, "name"))
        lbl = agnameof (v);
    else {
        lbl = agget (v, s);
        if (!lbl) lbl = "";
    }
    return lbl;
}
 
static void renderSelectedNodes(Agraph_t * g)
{
    Agnode_t *v;
    xdot * x;
    glCompPoint pos;
    Agsym_t* l_color_attr = GG_nodelabelcolor(g);
    glCompColor c;
    int defaultNodeShape;
    float nodeSize;
 
    glCompColorxlate(&c,agxget(g,l_color_attr));
 
    defaultNodeShape=getAttrBool(g,g,"defaultnodeshape",0);
    if(defaultNodeShape==0)
        glBegin(GL_POINTS);
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        if(!ND_selected(v))
            continue;
        x=parseXdotwithattrs(v);
        draw_xdot(x,-1);
        if(x)
            freeXDot (x);
    }
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        if(!ND_selected(v))
            continue;
        glColor4f(view->selectedNodeColor.R, view->selectedNodeColor.G,view->selectedNodeColor.B, view->selectedNodeColor.A);
        pos = ND_A(v);
        nodeSize = ND_size(v);
 
        if (defaultNodeShape == 0) 
            glVertex3f(pos.x, pos.y, pos.z + 0.001f);
        else if (defaultNodeShape == 1) 
            drawCircle(pos.x, pos.y, nodeSize, pos.z + 0.001f);
    }
    if(defaultNodeShape==0)
        glEnd();
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        if(!ND_selected(v))
            continue;
        if (ND_printLabel(v)==1)
        {
            pos = ND_A(v);
            glColor4f(c.R, c.G,c.B, c.A);
            glprintfglut(view->glutfont, pos.x, pos.y, pos.z + 0.002f, labelOf(g, v));
        }
    }
}
 
 
 
static void renderNodes(Agraph_t * g)
{
    Agnode_t *v;
    glCompPoint pos;
    Agsym_t* pos_attr = GN_pos(g);
    Agsym_t* size_attr = GN_size(g);
    Agsym_t* selected_attr = GN_selected(g);
    float nodeSize;
    glCompColor c;
    xdot * x;
    int ind;
 
    const int defaultNodeShape=getAttrInt(g, g, "defaultnodeshape", 0);
 
    x=parseXdotwithattrs(g);
    if (x) {
        draw_xdot(x, -0.2);
        freeXDot (x);
    }
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
            if (!object_color(v, &(glCompColor){0}))
                continue;
            x=parseXdotwithattrs(v);
            draw_xdot(x, -0.1);
 
            if(x)
                freeXDot (x);
    }
 
    if(defaultNodeShape==0)
        glBegin(GL_POINTS);
 
    ind=0;
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        ND_TVref(v) = ind;
        if(!object_color(v,&c))
        {
            ND_visible(v) = 0;
            continue;
        }
        else
            ND_visible(v) = 1;
 
        if(l_int(v, selected_attr,0))
        {
            ND_selected(v) = 1;
        }
        glColor4f(c.R,c.G,c.B,c.A);         
        pos=getPointFromStr(agxget(v, pos_attr));
        nodeSize = l_float(v, size_attr, 0);
 
        ND_A(v) = pos;
 
        if (nodeSize > 0)
            nodeSize=nodeSize*view->nodeScale;
        else
            nodeSize=view->nodeScale;
        if(defaultNodeShape==0)
            nodeSize=1;
        ND_size(v) = nodeSize;
        if (defaultNodeShape == 0) 
            glVertex3f(pos.x,pos.y,pos.z);
        else if (defaultNodeShape == 1) 
            drawCircle(pos.x,pos.y,nodeSize,pos.z);
        ind++;
    }
    if(defaultNodeShape==0)
        glEnd();
}
 
 
static void renderSelectedEdges(Agraph_t * g)
{
 
    Agedge_t *e;
    Agnode_t *v;
    xdot * x;
    glCompPoint posT;   /*Tail position*/
    glCompPoint posH;   /*Head position*/
    /*xdots tend to be drawn as background shapes,that is why they are being rendered before edges*/
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        for (e = agfstout(g, v); e; e = agnxtout(g, e)) 
        {
            if(!ED_selected(e))
                continue;
            if (!object_color(e, &(glCompColor){0}))
                continue;
 
            x=parseXdotwithattrs(e);
            draw_xdot(x,0);
            if(x)
                freeXDot (x);
        }
    }
 
    glBegin(GL_LINES);
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        for (e = agfstout(g, v); e; e = agnxtout(g, e)) 
        {
            if(!ED_selected(e))
                continue;
 
            if (!object_color(e, &(glCompColor){0}))
                continue;
            glColor4f(1,0,0,1);     
            posT = ED_posTail(e);
            posH = ED_posHead(e);
            posT.z +=0.01f;
            posH.z +=0.01f;
            draw_edge(posT, posH);
        }
    }
    glEnd();
}
 
/* skipWS:
 * Skip whitespace
 */
static char* skipWS (char* p)
{
    while (gv_isspace(*p)) p++;
    return p;
}
 
/* skipNWS:
 * Skip non-whitespace
 */
static char* skipNWS (char* p)
{
    while (*p && !gv_isspace(*p)) p++;
    return p;
}
 
/* readPoint:
 * Parse x,y[,z] and store in pt.
 * If z is not specified, set to 0.
 * Return pointer to next character after reading the point.
 * Return NULL on error.
 */
static char* readPoint (char* p, xdot_point* pt)
{
    char* endp;
 
    pt->z = 0;
    pt->x = strtod (p, &endp);
    if (p == endp) {
        return 0;
    }
    else
        p = endp;
    if (*p == ',') p++;
    else return 0;
 
    pt->y = strtod (p, &endp);
    if (p == endp) {
        return 0;
    }
    else
        p = endp;
    if ((*p == ' ') || (*p == '\0')) return p;
    else if (*p == ',') p++;
    else return 0;
 
    pt->z = strtod (p, &endp);
    if (p == endp) {
        return 0;
    }
    else
        return endp;
}
 
/* countPoints:
 * count number of points in pos attribute; store in cntp;
 * check for e and s points; store if found and increment number of
 * points by 3 for each.
 * return start of point list (skip over e and s points).
 * return NULL on failure
 */
static char *countPoints(char *pos, int *have_sp, xdot_point *sp, int *have_ep,
                         xdot_point *ep, size_t *cntp) {
    size_t cnt = 0;
    char* p;
 
    pos = skipWS (pos);
    if (*pos == 's') {
        if ((pos = readPoint (pos+2, sp))) {
            *have_sp = 1;
            cnt += 3;
        }
        else
            return 0;
    }
    else
        *have_sp = 0;
 
    pos = skipWS (pos);
    if (*pos == 'e') {
        if ((pos = readPoint (pos+2, ep))) {
            *have_ep = 1;
            cnt += 3;
        }
        else
            return 0;
    }
    else
        *have_ep = 0;
 
    p = pos = skipWS (pos);
 
    while (*p) {
        cnt++;
        p = skipNWS (p);
        p = skipWS (p);
    }
    *cntp = cnt;
 
    return pos;
}
 
/* storePoints:
 * read comma-separated list of points
 * and store them in ps
 * Assumes enough storage is available.
 * return -1 on error
 */
static int storePoints (char* pos, xdot_point* ps)
{
    
    while (*pos) {
        if ((pos = readPoint (pos, ps))) {
            ps++;
            pos = skipWS(pos);
        }
        else
            return -1;
    }
    return 0;
}
 
/* makeXDotSpline:
 * Generate an xdot representation of an edge's pos attribute
 */
static xdot* makeXDotSpline (char* pos)
{
    xdot_point s, e;
    int v, have_s, have_e;
    size_t cnt;
    static const size_t sz = sizeof(sdot_op);
 
    if (*pos == '\0') return NULL;
 
    pos = countPoints (pos, &have_s, &s, &have_e, &e, &cnt);
    if (pos == 0) return NULL;
 
    xdot_point* pts = gv_calloc(cnt, sizeof(xdot_point));
    if (have_s) {
        v = storePoints (pos, pts+3);
        pts[0] = pts[1] = s;
        pts[2] = pts[3];
    }
    else
        v = storePoints (pos, pts);
    if (v) {
        free (pts);
        return NULL;
    }
 
    if (have_e) {
        pts[cnt-1] = pts[cnt-2] = e;
        pts[cnt-3] = pts[cnt-4];
    }
 
    xdot_op* op = gv_calloc(sz, sizeof(char));
    op->kind = xd_unfilled_bezier;
    op->drawfunc = OpFns[xop_bezier];
    op->u.bezier.cnt = cnt; 
    op->u.bezier.pts = pts; 
 
    xdot* xd = gv_alloc(sizeof(xdot));
    xd->cnt = 1;
    xd->sz = sz;
    xd->ops = op;
 
    return xd;
}
 
typedef void (*edgefn) (Agraph_t *, Agedge_t*, glCompColor);
 
static void renderEdgesFn (Agraph_t * g, edgefn ef, int skipSelected)
{
    Agedge_t *e;
    Agnode_t *v;
    glCompColor c;
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        for (e = agfstout(g, v); e; e = agnxtout(g, e)) 
        {
            if ((ND_visible(agtail(e))==0) || (ND_visible(aghead(e))==0))
                continue;
 
            if(!object_color(e,&c)) {
                continue;
            }
            if (ED_selected(e) && skipSelected)
                continue;
 
            ef (g, e, c);
        }
    }
}
 
static void edge_xdot (Agraph_t* g, Agedge_t* e, glCompColor c)
{
    (void)g;
    (void)c;
 
    xdot * x;
    x=parseXdotwithattrs(e);
    draw_xdot(x,0);
    if(x)
        freeXDot (x);
}
 
static void edge_seg (Agraph_t* g, Agedge_t* e, glCompColor c)
{
    Agsym_t* pos_attr = GN_pos(g);
 
    glColor4f(c.R,c.G,c.B,c.A);    
    // tail position
    const glCompPoint posT = getPointFromStr(agxget(agtail(e), pos_attr));
    // head position
    const glCompPoint posH = getPointFromStr(agxget(aghead(e), pos_attr));
    draw_edge(posT, posH);
    ED_posTail(e) = posT;
    ED_posHead(e) = posH;
}
 
static void edge_spline (Agraph_t* g, Agedge_t* e, glCompColor c)
{
    Agsym_t* pos_attr_e = GE_pos(g);
 
    glColor4f(c.R,c.G,c.B,c.A);    
    xdot *const x = makeXDotSpline(agxget(e, pos_attr_e));
    if (x) {
        draw_xdot(x,0);
        freeXDot (x);
    }
}
 
static void renderEdges(Agraph_t * g)
{
    Agsym_t* pos_attr_e = GE_pos(g);
    int drawSegs = !(pos_attr_e && view->drawSplines);
    /*xdots tend to be drawn as background shapes,that is why they are being rendered before edges*/
 
    renderEdgesFn (g, edge_xdot, 0);
 
    if (drawSegs) {
        glBegin(GL_LINES);
        renderEdgesFn (g, edge_seg, 1);
        glEnd();
    }
    else
        renderEdgesFn (g, edge_spline, 1);
}
 
static void renderNodeLabels(Agraph_t * g)
{
    Agnode_t *v;
    glCompPoint pos;
    Agsym_t* data_attr = GN_labelattribute(g);
    Agsym_t* l_color_attr = GG_nodelabelcolor(g);
    glCompColor c;
 
    glCompColorxlate(&c,agxget(g,l_color_attr));
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
         if(ND_visible(v)==0)
            continue;
         if(ND_selected(v)==1)
            continue;
 
        pos = ND_A(v);
        glColor4f(c.R,c.G,c.B,c.A);
        if(!data_attr)
            glprintfglut(view->glutfont,pos.x,pos.y,pos.z,agnameof(v));
        else
            glprintfglut(view->glutfont,pos.x,pos.y,pos.z,agxget(v,data_attr));
    }
}
 
static void renderEdgeLabels(Agraph_t * g)
{
    Agedge_t *e;
    Agnode_t *v;
    glCompPoint posT;
    glCompPoint posH;
    Agsym_t* data_attr = GE_labelattribute(g);
    Agsym_t* l_color_attr = GG_edgelabelcolor(g);
    glCompColor c;
 
    glCompColorxlate(&c,agxget(g,l_color_attr));
 
    if(!data_attr || !l_color_attr)
        return;
 
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) 
    {
        for (e = agfstout(g, v); e; e = agnxtout(g, e)) 
        {
 
            if (ND_visible(v)==0)
                continue;
 
            posT = ED_posTail(e);
            posH = ED_posHead(e);
            glColor4f(c.R,c.G,c.B,c.A);
            float x = posH.x + (posT.x - posH.x) / 2;
            float y = posH.y + (posT.y - posH.y) / 2;
            float z = posH.z + (posT.z - posH.z) / 2;
            glprintfglut(view->glutfont,x,y,z,agxget(e,data_attr));
 
        }
    }
}
 
 
 
 
 
static void cacheNodes(Agraph_t * g,topview* t)
{
    if (t->cache.node_id != UINT_MAX) // clean existing cache
        glDeleteLists(t->cache.node_id,1);
    t->cache.node_id=glGenLists(1);
    glNewList(t->cache.node_id,GL_COMPILE);
    renderNodes(g);
    glEndList();
 
 
 
 
}
static void cacheEdges(Agraph_t * g,topview* t)
{
    if (t->cache.edge_id != UINT_MAX) // clean existing cache
        glDeleteLists(t->cache.edge_id,1);
    t->cache.edge_id=glGenLists(1);
    glNewList(t->cache.edge_id,GL_COMPILE);
    renderEdges(g);
    glEndList();
 
 
}
void cacheSelectedEdges(Agraph_t * g,topview* t)
{
    if (t->cache.seledge_id != UINT_MAX) // clean existing cache
        glDeleteLists(t->cache.seledge_id,1);
    t->cache.seledge_id=glGenLists(1);
    glNewList(t->cache.seledge_id,GL_COMPILE);
    renderSelectedEdges(g);
    glEndList();
 
 
}
void cacheSelectedNodes(Agraph_t * g,topview* t)
{
    if (t->cache.selnode_id != UINT_MAX) // clean existing cache
        glDeleteLists(t->cache.selnode_id,1);
    t->cache.selnode_id=glGenLists(1);
    glNewList(t->cache.selnode_id,GL_COMPILE);
    renderSelectedNodes(g);
    glEndList();
}
static void cacheNodeLabels(Agraph_t * g,topview* t)
{
    if (t->cache.nodelabel_id != UINT_MAX) // clean existing cache
        glDeleteLists(t->cache.nodelabel_id,1);
    t->cache.nodelabel_id=glGenLists(1);
    glNewList(t->cache.nodelabel_id,GL_COMPILE);
    renderNodeLabels(g);
    glEndList();
}
static void cacheEdgeLabels(Agraph_t * g,topview* t)
{
    if (t->cache.edgelabel_id != UINT_MAX) // clean existing cache
        glDeleteLists(t->cache.edgelabel_id,1);
    t->cache.edgelabel_id=glGenLists(1);
    glNewList(t->cache.edgelabel_id,GL_COMPILE);
    renderEdgeLabels(g);
    glEndList();
}
 
void updateSmGraph(Agraph_t * g,topview* t)
{
    Agnode_t *v;
    Agedge_t *e;
    float eLength=0;
    float totalELength=0;
 
    t->Nodecount=0;
    t->maxedgelen=0;
 
    t->global_z=0;
    t->sel.selPoly = (glCompPoly_t){0};
 
    if(!t)
        return ;
    /*Node Loop*/
    for (v = agfstnode(g); v; v = agnxtnode(g, v)) {
        for (e = agfstout(g, v); e; e = agnxtout(g, e)) 
        {
            eLength=getEdgeLength(e);
            if(eLength > t->maxedgelen)
                t->maxedgelen=eLength;
            totalELength += eLength;
        }
        t->Nodecount++;
 
    }
    aginit(g, AGNODE, "nodeRec", sizeof(nodeRec), false);
    aginit(g, AGEDGE, "edgeRec", sizeof(edgeRec), false);
 
    set_boundaries(g);
    view->Topview=t;
 
 
    /*render nodes once to get set some attributes set,THIS IS A HACK, FIX IT*/
    renderNodes(g);
    cacheEdges(g,t);
    cacheSelectedEdges(g,t);
    cacheNodes(g,t);
    cacheSelectedNodes(g,t);
    cacheEdgeLabels(g,t);
    cacheNodeLabels(g,t);
}
void initSmGraph(Agraph_t * g,topview* rv)
{
    /*create attribute list*/
    rv->attributes=load_attr_list(view->g[view->activeGraph]);
 
    // set topological fisheye to NULL
    rv->fisheyeParams.h = NULL;
 
    rv->fisheyeParams.active = 0;
    rv->cache.node_id = UINT_MAX;
    rv->cache.selnode_id = UINT_MAX;
    rv->cache.edge_id = UINT_MAX;
    rv->cache.seledge_id = UINT_MAX;
    rv->sel.selectEdges = false;
    rv->sel.selectNodes = true;
 
    updateSmGraph(g,rv);
}
 
void renderSmGraph(topview* t)
{
    // We would like to have blending affect where node and edge overlap. To
    // achieve this, depth test should be turned off.
 
    glEnable(GL_POINT_SMOOTH);
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_DEPTH);
 
    if(view->drawedges)
    {
        glCallList(t->cache.edge_id);
        glCallList(t->cache.seledge_id);
        if(view->drawedgelabels)
        {
            if(view->zoom*-1 <  t->fitin_zoom /(float)view->labelnumberofnodes*-1) 
                    glCallList(t->cache.edgelabel_id);
 
        }
    }
    if(view->drawnodes)
    {
        glPointSize(view->nodeScale*t->fitin_zoom/view->zoom);
        glCallList(t->cache.node_id);
        glCallList(t->cache.selnode_id);
        if(view->drawnodelabels)
        {
            if(view->zoom*-1 <  t->fitin_zoom /(float)view->labelnumberofnodes*-1) 
                glCallList(t->cache.nodelabel_id);
        }
    }
 
}