Actual source code: dtri.c

petsc-3.4.4 2014-03-13
  2: /*
  3:        Provides the calling sequences for all the basic PetscDraw routines.
  4: */
  5: #include <petsc-private/drawimpl.h>  /*I "petscdraw.h" I*/

  9: /*@
 10:    PetscDrawTriangle - PetscDraws a triangle  onto a drawable.

 12:    Not Collective

 14:    Input Parameters:
 15: +  draw - the drawing context
 16: .  x1,y1,x2,y2,x3,y3 - the coordinates of the vertices
 17: -  c1,c2,c3 - the colors of the three vertices in the same order as the xi,yi

 19:    Level: beginner

 21:    Concepts: drawing^triangle
 22:    Concepts: graphics^triangle
 23:    Concepts: triangle

 25: @*/
 26: PetscErrorCode  PetscDrawTriangle(PetscDraw draw,PetscReal x1,PetscReal y_1,PetscReal x2,PetscReal y2,PetscReal x3,PetscReal y3,int c1,int c2,int c3)
 27: {
 29:   PetscBool      isnull;

 33:   PetscObjectTypeCompare((PetscObject)draw,PETSC_DRAW_NULL,&isnull);
 34:   if (isnull) return(0);
 35:   (*draw->ops->triangle)(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
 36:   return(0);
 37: }


 42: /*@
 43:        PetscDrawScalePopup - PetscDraws a contour scale window.

 45:      Collective on PetscDraw

 47:   Input Parameters:
 48: +    popup - the window (often a window obtained via PetscDrawGetPopup()
 49: .    min - minimum value being plotted
 50: -    max - maximum value being plotted

 52:   Level: intermediate

 54:   Notes:
 55:      All processors that share the draw MUST call this routine

 57: @*/
 58: PetscErrorCode  PetscDrawScalePopup(PetscDraw popup,PetscReal min,PetscReal max)
 59: {
 60:   PetscReal      xl = 0.0,yl = 0.0,xr = 2.0,yr = 1.0,value;
 62:   int            i,c = PETSC_DRAW_BASIC_COLORS,rank;
 63:   char           string[32];
 64:   MPI_Comm       comm;

 67:   PetscDrawCheckResizedWindow(popup);
 68:   PetscObjectGetComm((PetscObject)popup,&comm);
 69:   MPI_Comm_rank(comm,&rank);
 70:   if (rank) return(0);

 72:   for (i=0; i<10; i++) {
 73:     PetscDrawRectangle(popup,xl,yl,xr,yr,c,c,c,c);

 75:     yl += .1; yr += .1;
 76:     c = (int)((double)c + (245. - PETSC_DRAW_BASIC_COLORS)/9.);
 77:   }
 78:   for (i=0; i<10; i++) {
 79:     value = min + i*(max-min)/9.0;
 80:     /* look for a value that should be zero, but is not due to round-off */
 81:     if (PetscAbsReal(value) < 1.e-10 && max-min > 1.e-6) value = 0.0;
 82:     sprintf(string,"%18.16e",(double)value);
 83:     PetscDrawString(popup,.2,.02 + i/10.0,PETSC_DRAW_BLACK,string);
 84:   }
 85:   PetscDrawSetTitle(popup,"Contour Scale");
 86:   PetscDrawFlush(popup);
 87:   return(0);
 88: }

 90: typedef struct {
 91:   int       m,n;
 92:   PetscReal *x,*y,min,max,*v;
 93:   PetscBool showgrid;
 94: } ZoomCtx;

 98: static PetscErrorCode PetscDrawTensorContour_Zoom(PetscDraw win,void *dctx)
 99: {
101:   int            i;
102:   ZoomCtx        *ctx = (ZoomCtx*)dctx;

105:   PetscDrawTensorContourPatch(win,ctx->m,ctx->n,ctx->x,ctx->y,ctx->max,ctx->min,ctx->v);
106:   if (ctx->showgrid) {
107:     for (i=0; i<ctx->m; i++) {
108:       PetscDrawLine(win,ctx->x[i],ctx->y[0],ctx->x[i],ctx->y[ctx->n-1],PETSC_DRAW_BLACK);
109:     }
110:     for (i=0; i<ctx->n; i++) {
111:       PetscDrawLine(win,ctx->x[0],ctx->y[i],ctx->x[ctx->m-1],ctx->y[i],PETSC_DRAW_BLACK);
112:     }
113:   }
114:   return(0);
115: }

119: /*@C
120:    PetscDrawTensorContour - PetscDraws a contour plot for a two-dimensional array
121:    that is stored as a PETSc vector.

123:    Collective on PetscDraw, but PetscDraw must be sequential

125:    Input Parameters:
126: +   win   - the window to draw in
127: .   m,n   - the global number of mesh points in the x and y directions
128: .   xi,yi - the locations of the global mesh points (optional, use NULL
129:             to indicate uniform spacing on [0,1])
130: -   V     - the values

132:    Options Database Keys:
133: +  -draw_x_shared_colormap - Indicates use of private colormap
134: -  -draw_contour_grid - PetscDraws grid contour

136:    Level: intermediate

138:    Concepts: contour plot
139:    Concepts: drawing^contour plot

141: .seealso: PetscDrawTensorContourPatch()

143: @*/
144: PetscErrorCode  PetscDrawTensorContour(PetscDraw win,int m,int n,const PetscReal xi[],const PetscReal yi[],PetscReal *v)
145: {
147:   int            N = m*n;
148:   PetscBool      isnull;
149:   PetscDraw      popup;
150:   MPI_Comm       comm;
151:   int            xin=1,yin=1,i;
152:   PetscMPIInt    size;
153:   PetscReal      h;
154:   ZoomCtx        ctx;

157:   PetscDrawIsNull(win,&isnull); if (isnull) return(0);
158:   PetscObjectGetComm((PetscObject)win,&comm);
159:   MPI_Comm_size(comm,&size);
160:   if (size > 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"May only be used with single processor PetscDraw");
161:   if (N <= 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"n %d and m %d must be positive",m,n);

163:   /* create scale window */
164:   PetscDrawGetPopup(win,&popup);
165:   PetscDrawCheckResizedWindow(win);

167:   ctx.v   = v;
168:   ctx.m   = m;
169:   ctx.n   = n;
170:   ctx.max = ctx.min = v[0];
171:   for (i=0; i<N; i++) {
172:     if (ctx.max < ctx.v[i]) ctx.max = ctx.v[i];
173:     if (ctx.min > ctx.v[i]) ctx.min = ctx.v[i];
174:   }
175:   if (ctx.max - ctx.min < 1.e-7) {ctx.min -= 5.e-8; ctx.max += 5.e-8;}

177:   /* PetscDraw the scale window */
178:   if (popup) {PetscDrawScalePopup(popup,ctx.min,ctx.max);}

180:   ctx.showgrid = PETSC_FALSE;
181:   PetscOptionsGetBool(NULL,"-draw_contour_grid",&ctx.showgrid,NULL);

183:   /* fill up x and y coordinates */
184:   if (!xi) {
185:     xin      = 0;
186:     PetscMalloc(ctx.m*sizeof(PetscReal),&ctx.x);
187:     h        = 1.0/(ctx.m-1);
188:     ctx.x[0] = 0.0;
189:     for (i=1; i<ctx.m; i++) ctx.x[i] = ctx.x[i-1] + h;
190:   } else ctx.x = (PetscReal*)xi;

192:   if (!yi) {
193:     yin      = 0;
194:     PetscMalloc(ctx.n*sizeof(PetscReal),&ctx.y);
195:     h        = 1.0/(ctx.n-1);
196:     ctx.y[0] = 0.0;
197:     for (i=1; i<ctx.n; i++) ctx.y[i] = ctx.y[i-1] + h;
198:   } else ctx.y = (PetscReal*)yi;

200:   PetscDrawZoom(win,(PetscErrorCode (*)(PetscDraw,void*))PetscDrawTensorContour_Zoom,&ctx);

202:   if (!xin) {PetscFree(ctx.x);}
203:   if (!yin) {PetscFree(ctx.y);}
204:   return(0);
205: }

209: /*@
210:    PetscDrawTensorContourPatch - PetscDraws a rectangular patch of a contour plot
211:    for a two-dimensional array.

213:    Not Collective

215:    Input Parameters:
216: +  win - the window to draw in
217: .  m,n - the number of local mesh points in the x and y direction
218: .  x,y - the locations of the local mesh points
219: .  max,min - the maximum and minimum value in the entire contour
220: -  v - the data

222:    Options Database Keys:
223: .  -draw_x_shared_colormap - Activates private colormap

225:    Level: advanced

227:    Note:
228:    This is a lower level support routine, usually the user will call
229:    PetscDrawTensorContour().

231:    Concepts: contour plot

233: .seealso: PetscDrawTensorContour()

235: @*/
236: PetscErrorCode  PetscDrawTensorContourPatch(PetscDraw draw,int m,int n,PetscReal *x,PetscReal *y,PetscReal max,PetscReal min,PetscReal *v)
237: {
239:   int            c1,c2,c3,c4,i,j;
240:   PetscReal      x1,x2,x3,x4,y_1,y2,y3,y4,scale;

243:   scale = (245.0 - PETSC_DRAW_BASIC_COLORS)/(max - min);

245:   /* PetscDraw the contour plot patch */
246:   for (j=0; j<n-1; j++) {
247:     for (i=0; i<m-1; i++) {
248:       x1 = x[i];  y_1 = y[j]; c1 = (int)(PETSC_DRAW_BASIC_COLORS + scale*(v[i+j*m] - min));
249:       x2 = x[i+1];y2 = y_1;   c2 = (int)(PETSC_DRAW_BASIC_COLORS + scale*(v[i+j*m+1]-min));
250:       x3 = x2;    y3 = y[j+1];c3 = (int)(PETSC_DRAW_BASIC_COLORS + scale*(v[i+j*m+1+m]-min));
251:       x4 = x1;    y4 = y3;    c4 = (int)(PETSC_DRAW_BASIC_COLORS + scale*(v[i+j*m+m]-min));

253:       PetscDrawTriangle(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
254:       PetscDrawTriangle(draw,x1,y_1,x3,y3,x4,y4,c1,c3,c4);
255:     }
256:   }
257:   return(0);
258: }