Date: 2022-03-31T04:45:59+00:00

Actual source code: dtri.c

      2: /*
      3:        Provides the calling sequences for all the basic PetscDraw routines.
      4: */
      5: #include <petsc/private/drawimpl.h>

      7: /*@
      8:    PetscDrawTriangle - PetscDraws a triangle  onto a drawable.

     10:    Not Collective

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

     17:    Level: beginner

     19: .seealso: PetscDrawLine(), PetscDrawRectangle(), PetscDrawEllipse(), PetscDrawMarker(), PetscDrawPoint(), PetscDrawArrow()
     20: @*/
     21: PetscErrorCode  PetscDrawTriangle(PetscDraw draw,PetscReal x1,PetscReal y_1,PetscReal x2,PetscReal y2,PetscReal x3,PetscReal y3,int c1,int c2,int c3)
     22: {
     25:   (*draw->ops->triangle)(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
     26:   return 0;
     27: }

     29: /*@
     30:    PetscDrawScalePopup - draws a contour scale window.

     32:    Collective on PetscDraw

     34:    Input Parameters:
     35: +  popup - the window (often a window obtained via PetscDrawGetPopup()
     36: .  min - minimum value being plotted
     37: -  max - maximum value being plotted

     39:    Level: intermediate

     41:    Notes:
     42:     All processors that share the draw MUST call this routine

     44: .seealso: PetscDrawGetPopup(), PetscDrawTensorContour()

     46: @*/
     47: PetscErrorCode  PetscDrawScalePopup(PetscDraw popup,PetscReal min,PetscReal max)
     48: {
     49:   PetscBool      isnull;
     50:   PetscReal      xl = 0.0,yl = 0.0,xr = 1.0,yr = 1.0;
     51:   PetscMPIInt    rank;
     52:   int            i;
     53:   char           string[32];

     56:   if (!popup) return 0;
     58:   PetscDrawIsNull(popup,&isnull);
     59:   if (isnull) return 0;
     60:   MPI_Comm_rank(PetscObjectComm((PetscObject)popup),&rank);

     62:   PetscDrawCheckResizedWindow(popup);
     63:   PetscDrawClear(popup);
     64:   PetscDrawSetTitle(popup,"Contour Scale");
     65:   PetscDrawSetCoordinates(popup,xl,yl,xr,yr);
     66:   PetscDrawCollectiveBegin(popup);
     67:   if (rank == 0) {
     68:     for (i=0; i<10; i++) {
     69:       int c = PetscDrawRealToColor((PetscReal)i/9,0,1);
     70:       PetscDrawRectangle(popup,xl,yl,xr,yr,c,c,c,c);
     71:       yl += 0.1;
     72:     }
     73:     for (i=0; i<10; i++) {
     74:       PetscReal value = min + i*(max-min)/9;
     75:       /* look for a value that should be zero, but is not due to round-off */
     76:       if (PetscAbsReal(value) < 1.e-10 && max-min > 1.e-6) value = 0.0;
     77:       PetscSNPrintf(string,sizeof(string),"%18.16e",(double)value);
     78:       PetscDrawString(popup,0.2,0.02+i/10.0,PETSC_DRAW_BLACK,string);
     79:     }
     80:   }
     81:   PetscDrawCollectiveEnd(popup);
     82:   PetscDrawFlush(popup);
     83:   PetscDrawSave(popup);
     84:   return 0;
     85: }

     87: typedef struct {
     88:   int       m,n;
     89:   PetscReal *x,*y,min,max,*v;
     90:   PetscBool showgrid;
     91: } ZoomCtx;

     93: static PetscErrorCode PetscDrawTensorContour_Zoom(PetscDraw win,void *dctx)
     94: {
     95:   int            i;
     96:   ZoomCtx        *ctx = (ZoomCtx*)dctx;

     98:   PetscDrawTensorContourPatch(win,ctx->m,ctx->n,ctx->x,ctx->y,ctx->min,ctx->max,ctx->v);
     99:   if (ctx->showgrid) {
    100:     for (i=0; i<ctx->m; i++) {
    101:       PetscDrawLine(win,ctx->x[i],ctx->y[0],ctx->x[i],ctx->y[ctx->n-1],PETSC_DRAW_BLACK);
    102:     }
    103:     for (i=0; i<ctx->n; i++) {
    104:       PetscDrawLine(win,ctx->x[0],ctx->y[i],ctx->x[ctx->m-1],ctx->y[i],PETSC_DRAW_BLACK);
    105:     }
    106:   }
    107:   return 0;
    108: }

    110: /*@C
    111:    PetscDrawTensorContour - PetscDraws a contour plot for a two-dimensional array
    112:    that is stored as a PETSc vector.

    114:    Collective on PetscDraw, but PetscDraw must be sequential

    116:    Input Parameters:
    117: +   draw  - the draw context
    118: .   m,n   - the global number of mesh points in the x and y directions
    119: .   xi,yi - the locations of the global mesh points (optional, use NULL
    120:             to indicate uniform spacing on [0,1])
    121: -   V     - the values

    123:    Options Database Keys:
    124: +  -draw_x_shared_colormap - Indicates use of private colormap
    125: -  -draw_contour_grid - PetscDraws grid contour

    127:    Level: intermediate

    129: .seealso: PetscDrawTensorContourPatch(), PetscDrawScalePopup()

    131: @*/
    132: PetscErrorCode  PetscDrawTensorContour(PetscDraw draw,int m,int n,const PetscReal xi[],const PetscReal yi[],PetscReal *v)
    133: {
    134:   int            N = m*n;
    135:   PetscBool      isnull;
    136:   PetscDraw      popup;
    137:   int            xin=1,yin=1,i;
    138:   PetscMPIInt    size;
    139:   PetscReal      h;
    140:   ZoomCtx        ctx;

    143:   PetscDrawIsNull(draw,&isnull);
    144:   if (isnull) return 0;
    145:   MPI_Comm_size(PetscObjectComm((PetscObject)draw),&size);

    149:   ctx.v   = v;
    150:   ctx.m   = m;
    151:   ctx.n   = n;
    152:   ctx.max = ctx.min = v[0];
    153:   for (i=0; i<N; i++) {
    154:     if (ctx.max < ctx.v[i]) ctx.max = ctx.v[i];
    155:     if (ctx.min > ctx.v[i]) ctx.min = ctx.v[i];
    156:   }
    157:   if (ctx.max - ctx.min < 1.e-7) {ctx.min -= 5.e-8; ctx.max += 5.e-8;}

    159:   /* PetscDraw the scale window */
    160:   PetscDrawGetPopup(draw,&popup);
    161:   PetscDrawScalePopup(popup,ctx.min,ctx.max);

    163:   ctx.showgrid = PETSC_FALSE;
    164:   PetscOptionsGetBool(((PetscObject)draw)->options,NULL,"-draw_contour_grid",&ctx.showgrid,NULL);

    166:   /* fill up x and y coordinates */
    167:   if (!xi) {
    168:     xin      = 0;
    169:     PetscMalloc1(ctx.m,&ctx.x);
    170:     h        = 1.0/(ctx.m-1);
    171:     ctx.x[0] = 0.0;
    172:     for (i=1; i<ctx.m; i++) ctx.x[i] = ctx.x[i-1] + h;
    173:   } else ctx.x = (PetscReal*)xi;

    175:   if (!yi) {
    176:     yin      = 0;
    177:     PetscMalloc1(ctx.n,&ctx.y);
    178:     h        = 1.0/(ctx.n-1);
    179:     ctx.y[0] = 0.0;
    180:     for (i=1; i<ctx.n; i++) ctx.y[i] = ctx.y[i-1] + h;
    181:   } else ctx.y = (PetscReal*)yi;

    183:   PetscDrawZoom(draw,PetscDrawTensorContour_Zoom,&ctx);

    185:   if (!xin) PetscFree(ctx.x);
    186:   if (!yin) PetscFree(ctx.y);
    187:   return 0;
    188: }

    190: /*@
    191:    PetscDrawTensorContourPatch - PetscDraws a rectangular patch of a contour plot
    192:    for a two-dimensional array.

    194:    Not Collective

    196:    Input Parameters:
    197: +  draw - the draw context
    198: .  m,n - the number of local mesh points in the x and y direction
    199: .  x,y - the locations of the local mesh points
    200: .  min,max - the minimum and maximum value in the entire contour
    201: -  v - the data

    203:    Options Database Keys:
    204: .  -draw_x_shared_colormap - Activates private colormap

    206:    Level: advanced

    208:    Note:
    209:    This is a lower level support routine, usually the user will call
    210:    PetscDrawTensorContour().

    212: .seealso: PetscDrawTensorContour()

    214: @*/
    215: PetscErrorCode  PetscDrawTensorContourPatch(PetscDraw draw,int m,int n,PetscReal *x,PetscReal *y,PetscReal min,PetscReal max,PetscReal *v)
    216: {
    217:   int            c1,c2,c3,c4,i,j;
    218:   PetscReal      x1,x2,x3,x4,y_1,y2,y3,y4;

    221:   /* PetscDraw the contour plot patch */
    222:   for (j=0; j<n-1; j++) {
    223:     for (i=0; i<m-1; i++) {
    224:       x1 = x[i];   y_1 = y[j];  c1 = PetscDrawRealToColor(v[i+j*m],min,max);
    225:       x2 = x[i+1]; y2 = y_1;    c2 = PetscDrawRealToColor(v[i+j*m+1],min,max);
    226:       x3 = x2;     y3 = y[j+1]; c3 = PetscDrawRealToColor(v[i+j*m+1+m],min,max);
    227:       x4 = x1;     y4 = y3;     c4 = PetscDrawRealToColor(v[i+j*m+m],min,max);

    229:       PetscDrawTriangle(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
    230:       PetscDrawTriangle(draw,x1,y_1,x3,y3,x4,y4,c1,c3,c4);
    231:     }
    232:   }
    233:   return 0;
    234: }