Date: 2022-03-04T17:37:01+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: {

     27:   if (!draw->ops->triangle) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"This draw type %s does not support drawing triangles",((PetscObject)draw)->type_name);
     28:   (*draw->ops->triangle)(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
     29:   return(0);
     30: }

     32: /*@
     33:    PetscDrawScalePopup - draws a contour scale window.

     35:    Collective on PetscDraw

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

     42:    Level: intermediate

     44:    Notes:
     45:     All processors that share the draw MUST call this routine

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

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

     60:   if (!popup) return(0);
     62:   PetscDrawIsNull(popup,&isnull);
     63:   if (isnull) return(0);
     64:   MPI_Comm_rank(PetscObjectComm((PetscObject)popup),&rank);

     66:   PetscDrawCheckResizedWindow(popup);
     67:   PetscDrawClear(popup);
     68:   PetscDrawSetTitle(popup,"Contour Scale");
     69:   PetscDrawSetCoordinates(popup,xl,yl,xr,yr);
     70:   PetscDrawCollectiveBegin(popup);
     71:   if (rank == 0) {
     72:     for (i=0; i<10; i++) {
     73:       int c = PetscDrawRealToColor((PetscReal)i/9,0,1);
     74:       PetscDrawRectangle(popup,xl,yl,xr,yr,c,c,c,c);
     75:       yl += 0.1;
     76:     }
     77:     for (i=0; i<10; i++) {
     78:       PetscReal value = min + i*(max-min)/9;
     79:       /* look for a value that should be zero, but is not due to round-off */
     80:       if (PetscAbsReal(value) < 1.e-10 && max-min > 1.e-6) value = 0.0;
     81:       PetscSNPrintf(string,sizeof(string),"%18.16e",(double)value);
     82:       PetscDrawString(popup,0.2,0.02+i/10.0,PETSC_DRAW_BLACK,string);
     83:     }
     84:   }
     85:   PetscDrawCollectiveEnd(popup);
     86:   PetscDrawFlush(popup);
     87:   PetscDrawSave(popup);
     88:   return(0);
     89: }

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

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

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

    116: /*@C
    117:    PetscDrawTensorContour - PetscDraws a contour plot for a two-dimensional array
    118:    that is stored as a PETSc vector.

    120:    Collective on PetscDraw, but PetscDraw must be sequential

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

    129:    Options Database Keys:
    130: +  -draw_x_shared_colormap - Indicates use of private colormap
    131: -  -draw_contour_grid - PetscDraws grid contour

    133:    Level: intermediate

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

    137: @*/
    138: PetscErrorCode  PetscDrawTensorContour(PetscDraw draw,int m,int n,const PetscReal xi[],const PetscReal yi[],PetscReal *v)
    139: {
    141:   int            N = m*n;
    142:   PetscBool      isnull;
    143:   PetscDraw      popup;
    144:   int            xin=1,yin=1,i;
    145:   PetscMPIInt    size;
    146:   PetscReal      h;
    147:   ZoomCtx        ctx;

    151:   PetscDrawIsNull(draw,&isnull);
    152:   if (isnull) return(0);
    153:   MPI_Comm_size(PetscObjectComm((PetscObject)draw),&size);
    154:   if (size > 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"May only be used with single processor PetscDraw");
    155:   if (N <= 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"n %d and m %d must be positive",m,n);

    157:   ctx.v   = v;
    158:   ctx.m   = m;
    159:   ctx.n   = n;
    160:   ctx.max = ctx.min = v[0];
    161:   for (i=0; i<N; i++) {
    162:     if (ctx.max < ctx.v[i]) ctx.max = ctx.v[i];
    163:     if (ctx.min > ctx.v[i]) ctx.min = ctx.v[i];
    164:   }
    165:   if (ctx.max - ctx.min < 1.e-7) {ctx.min -= 5.e-8; ctx.max += 5.e-8;}

    167:   /* PetscDraw the scale window */
    168:   PetscDrawGetPopup(draw,&popup);
    169:   PetscDrawScalePopup(popup,ctx.min,ctx.max);

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

    174:   /* fill up x and y coordinates */
    175:   if (!xi) {
    176:     xin      = 0;
    177:     PetscMalloc1(ctx.m,&ctx.x);
    178:     h        = 1.0/(ctx.m-1);
    179:     ctx.x[0] = 0.0;
    180:     for (i=1; i<ctx.m; i++) ctx.x[i] = ctx.x[i-1] + h;
    181:   } else ctx.x = (PetscReal*)xi;

    183:   if (!yi) {
    184:     yin      = 0;
    185:     PetscMalloc1(ctx.n,&ctx.y);
    186:     h        = 1.0/(ctx.n-1);
    187:     ctx.y[0] = 0.0;
    188:     for (i=1; i<ctx.n; i++) ctx.y[i] = ctx.y[i-1] + h;
    189:   } else ctx.y = (PetscReal*)yi;

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

    193:   if (!xin) {PetscFree(ctx.x);}
    194:   if (!yin) {PetscFree(ctx.y);}
    195:   return(0);
    196: }

    198: /*@
    199:    PetscDrawTensorContourPatch - PetscDraws a rectangular patch of a contour plot
    200:    for a two-dimensional array.

    202:    Not Collective

    204:    Input Parameters:
    205: +  draw - the draw context
    206: .  m,n - the number of local mesh points in the x and y direction
    207: .  x,y - the locations of the local mesh points
    208: .  min,max - the minimum and maximum value in the entire contour
    209: -  v - the data

    211:    Options Database Keys:
    212: .  -draw_x_shared_colormap - Activates private colormap

    214:    Level: advanced

    216:    Note:
    217:    This is a lower level support routine, usually the user will call
    218:    PetscDrawTensorContour().

    220: .seealso: PetscDrawTensorContour()

    222: @*/
    223: PetscErrorCode  PetscDrawTensorContourPatch(PetscDraw draw,int m,int n,PetscReal *x,PetscReal *y,PetscReal min,PetscReal max,PetscReal *v)
    224: {
    226:   int            c1,c2,c3,c4,i,j;
    227:   PetscReal      x1,x2,x3,x4,y_1,y2,y3,y4;

    231:   /* PetscDraw the contour plot patch */
    232:   for (j=0; j<n-1; j++) {
    233:     for (i=0; i<m-1; i++) {
    234:       x1 = x[i];   y_1 = y[j];  c1 = PetscDrawRealToColor(v[i+j*m],min,max);
    235:       x2 = x[i+1]; y2 = y_1;    c2 = PetscDrawRealToColor(v[i+j*m+1],min,max);
    236:       x3 = x2;     y3 = y[j+1]; c3 = PetscDrawRealToColor(v[i+j*m+1+m],min,max);
    237:       x4 = x1;     y4 = y3;     c4 = PetscDrawRealToColor(v[i+j*m+m],min,max);

    239:       PetscDrawTriangle(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
    240:       PetscDrawTriangle(draw,x1,y_1,x3,y3,x4,y4,c1,c3,c4);
    241:     }
    242:   }
    243:   return(0);
    244: }