xref: /petsc/src/sys/classes/draw/interface/dtri.c (revision 95452b02e12c0ee11232c7ff2b24b568a8e07e43)
1 
2 /*
3        Provides the calling sequences for all the basic PetscDraw routines.
4 */
5 #include <petsc/private/drawimpl.h>  /*I "petscdraw.h" I*/
6 
7 /*@
8    PetscDrawTriangle - PetscDraws a triangle  onto a drawable.
9 
10    Not Collective
11 
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
16 
17    Level: beginner
18 
19    Concepts: drawing^triangle
20    Concepts: graphics^triangle
21    Concepts: triangle
22 
23 .seealso: PetscDrawLine(), PetscDrawRectangle(), PetscDrawEllipse(), PetscDrawMarker(), PetscDrawPoint(), PetscDrawArrow()
24 @*/
25 PetscErrorCode  PetscDrawTriangle(PetscDraw draw,PetscReal x1,PetscReal y_1,PetscReal x2,PetscReal y2,PetscReal x3,PetscReal y3,int c1,int c2,int c3)
26 {
27   PetscErrorCode ierr;
28 
29   PetscFunctionBegin;
30   PetscValidHeaderSpecific(draw,PETSC_DRAW_CLASSID,1);
31   if (!draw->ops->triangle) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"This draw type %s does not support drawing triangles",((PetscObject)draw)->type_name);
32   ierr = (*draw->ops->triangle)(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);CHKERRQ(ierr);
33   PetscFunctionReturn(0);
34 }
35 
36 /*@
37    PetscDrawScalePopup - draws a contour scale window.
38 
39    Collective on PetscDraw
40 
41    Input Parameters:
42 +  popup - the window (often a window obtained via PetscDrawGetPopup()
43 .  min - minimum value being plotted
44 -  max - maximum value being plotted
45 
46    Level: intermediate
47 
48    Notes:
49     All processors that share the draw MUST call this routine
50 
51 .seealso: PetscDrawGetPopup(), PetscDrawTensorContour()
52 
53 @*/
54 PetscErrorCode  PetscDrawScalePopup(PetscDraw popup,PetscReal min,PetscReal max)
55 {
56   PetscBool      isnull;
57   PetscReal      xl = 0.0,yl = 0.0,xr = 1.0,yr = 1.0;
58   PetscMPIInt    rank;
59   PetscErrorCode ierr;
60   int            i;
61   char           string[32];
62 
63   PetscFunctionBegin;
64   if (!popup) PetscFunctionReturn(0);
65   PetscValidHeaderSpecific(popup,PETSC_DRAW_CLASSID,1);
66   ierr = PetscDrawIsNull(popup,&isnull);CHKERRQ(ierr);
67   if (isnull) PetscFunctionReturn(0);
68   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)popup),&rank);CHKERRQ(ierr);
69 
70   ierr = PetscDrawCheckResizedWindow(popup);CHKERRQ(ierr);
71   ierr = PetscDrawClear(popup);CHKERRQ(ierr);
72   ierr = PetscDrawSetTitle(popup,"Contour Scale");CHKERRQ(ierr);
73   ierr = PetscDrawSetCoordinates(popup,xl,yl,xr,yr);CHKERRQ(ierr);
74   ierr = PetscDrawCollectiveBegin(popup);CHKERRQ(ierr);
75   if (!rank) {
76     for (i=0; i<10; i++) {
77       int c = PetscDrawRealToColor((PetscReal)i/9,0,1);
78       ierr = PetscDrawRectangle(popup,xl,yl,xr,yr,c,c,c,c);CHKERRQ(ierr);
79       yl += 0.1;
80     }
81     for (i=0; i<10; i++) {
82       PetscReal value = min + i*(max-min)/9;
83       /* look for a value that should be zero, but is not due to round-off */
84       if (PetscAbsReal(value) < 1.e-10 && max-min > 1.e-6) value = 0.0;
85       ierr = PetscSNPrintf(string,sizeof(string),"%18.16e",(double)value);CHKERRQ(ierr);
86       ierr = PetscDrawString(popup,0.2,0.02+i/10.0,PETSC_DRAW_BLACK,string);CHKERRQ(ierr);
87     }
88   }
89   ierr = PetscDrawCollectiveEnd(popup);CHKERRQ(ierr);
90   ierr = PetscDrawFlush(popup);CHKERRQ(ierr);
91   ierr = PetscDrawSave(popup);CHKERRQ(ierr);
92   PetscFunctionReturn(0);
93 }
94 
95 typedef struct {
96   int       m,n;
97   PetscReal *x,*y,min,max,*v;
98   PetscBool showgrid;
99 } ZoomCtx;
100 
101 static PetscErrorCode PetscDrawTensorContour_Zoom(PetscDraw win,void *dctx)
102 {
103   PetscErrorCode ierr;
104   int            i;
105   ZoomCtx        *ctx = (ZoomCtx*)dctx;
106 
107   PetscFunctionBegin;
108   ierr = PetscDrawTensorContourPatch(win,ctx->m,ctx->n,ctx->x,ctx->y,ctx->min,ctx->max,ctx->v);CHKERRQ(ierr);
109   if (ctx->showgrid) {
110     for (i=0; i<ctx->m; i++) {
111       ierr = PetscDrawLine(win,ctx->x[i],ctx->y[0],ctx->x[i],ctx->y[ctx->n-1],PETSC_DRAW_BLACK);CHKERRQ(ierr);
112     }
113     for (i=0; i<ctx->n; i++) {
114       ierr = PetscDrawLine(win,ctx->x[0],ctx->y[i],ctx->x[ctx->m-1],ctx->y[i],PETSC_DRAW_BLACK);CHKERRQ(ierr);
115     }
116   }
117   PetscFunctionReturn(0);
118 }
119 
120 /*@C
121    PetscDrawTensorContour - PetscDraws a contour plot for a two-dimensional array
122    that is stored as a PETSc vector.
123 
124    Collective on PetscDraw, but PetscDraw must be sequential
125 
126    Input Parameters:
127 +   draw  - the draw context
128 .   m,n   - the global number of mesh points in the x and y directions
129 .   xi,yi - the locations of the global mesh points (optional, use NULL
130             to indicate uniform spacing on [0,1])
131 -   V     - the values
132 
133    Options Database Keys:
134 +  -draw_x_shared_colormap - Indicates use of private colormap
135 -  -draw_contour_grid - PetscDraws grid contour
136 
137    Level: intermediate
138 
139    Concepts: contour plot
140    Concepts: drawing^contour plot
141 
142 .seealso: PetscDrawTensorContourPatch(), PetscDrawScalePopup()
143 
144 @*/
145 PetscErrorCode  PetscDrawTensorContour(PetscDraw draw,int m,int n,const PetscReal xi[],const PetscReal yi[],PetscReal *v)
146 {
147   PetscErrorCode ierr;
148   int            N = m*n;
149   PetscBool      isnull;
150   PetscDraw      popup;
151   int            xin=1,yin=1,i;
152   PetscMPIInt    size;
153   PetscReal      h;
154   ZoomCtx        ctx;
155 
156   PetscFunctionBegin;
157   PetscValidHeaderSpecific(draw,PETSC_DRAW_CLASSID,1);
158   ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr);
159   if (isnull) PetscFunctionReturn(0);
160   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)draw),&size);CHKERRQ(ierr);
161   if (size > 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"May only be used with single processor PetscDraw");
162   if (N <= 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"n %d and m %d must be positive",m,n);
163 
164   ctx.v   = v;
165   ctx.m   = m;
166   ctx.n   = n;
167   ctx.max = ctx.min = v[0];
168   for (i=0; i<N; i++) {
169     if (ctx.max < ctx.v[i]) ctx.max = ctx.v[i];
170     if (ctx.min > ctx.v[i]) ctx.min = ctx.v[i];
171   }
172   if (ctx.max - ctx.min < 1.e-7) {ctx.min -= 5.e-8; ctx.max += 5.e-8;}
173 
174   /* PetscDraw the scale window */
175   ierr = PetscDrawGetPopup(draw,&popup);CHKERRQ(ierr);
176   ierr = PetscDrawScalePopup(popup,ctx.min,ctx.max);CHKERRQ(ierr);
177 
178   ctx.showgrid = PETSC_FALSE;
179   ierr = PetscOptionsGetBool(((PetscObject)draw)->options,NULL,"-draw_contour_grid",&ctx.showgrid,NULL);CHKERRQ(ierr);
180 
181   /* fill up x and y coordinates */
182   if (!xi) {
183     xin      = 0;
184     ierr     = PetscMalloc1(ctx.m,&ctx.x);CHKERRQ(ierr);
185     h        = 1.0/(ctx.m-1);
186     ctx.x[0] = 0.0;
187     for (i=1; i<ctx.m; i++) ctx.x[i] = ctx.x[i-1] + h;
188   } else ctx.x = (PetscReal*)xi;
189 
190   if (!yi) {
191     yin      = 0;
192     ierr     = PetscMalloc1(ctx.n,&ctx.y);CHKERRQ(ierr);
193     h        = 1.0/(ctx.n-1);
194     ctx.y[0] = 0.0;
195     for (i=1; i<ctx.n; i++) ctx.y[i] = ctx.y[i-1] + h;
196   } else ctx.y = (PetscReal*)yi;
197 
198   ierr = PetscDrawZoom(draw,PetscDrawTensorContour_Zoom,&ctx);CHKERRQ(ierr);
199 
200   if (!xin) {ierr = PetscFree(ctx.x);CHKERRQ(ierr);}
201   if (!yin) {ierr = PetscFree(ctx.y);CHKERRQ(ierr);}
202   PetscFunctionReturn(0);
203 }
204 
205 /*@
206    PetscDrawTensorContourPatch - PetscDraws a rectangular patch of a contour plot
207    for a two-dimensional array.
208 
209    Not Collective
210 
211    Input Parameters:
212 +  draw - the draw context
213 .  m,n - the number of local mesh points in the x and y direction
214 .  x,y - the locations of the local mesh points
215 .  min,max - the minimum and maximum value in the entire contour
216 -  v - the data
217 
218    Options Database Keys:
219 .  -draw_x_shared_colormap - Activates private colormap
220 
221    Level: advanced
222 
223    Note:
224    This is a lower level support routine, usually the user will call
225    PetscDrawTensorContour().
226 
227    Concepts: contour plot
228 
229 .seealso: PetscDrawTensorContour()
230 
231 @*/
232 PetscErrorCode  PetscDrawTensorContourPatch(PetscDraw draw,int m,int n,PetscReal *x,PetscReal *y,PetscReal min,PetscReal max,PetscReal *v)
233 {
234   PetscErrorCode ierr;
235   int            c1,c2,c3,c4,i,j;
236   PetscReal      x1,x2,x3,x4,y_1,y2,y3,y4;
237 
238   PetscFunctionBegin;
239   PetscValidHeaderSpecific(draw,PETSC_DRAW_CLASSID,1);
240   /* PetscDraw the contour plot patch */
241   for (j=0; j<n-1; j++) {
242     for (i=0; i<m-1; i++) {
243       x1 = x[i];   y_1 = y[j];  c1 = PetscDrawRealToColor(v[i+j*m],min,max);
244       x2 = x[i+1]; y2 = y_1;    c2 = PetscDrawRealToColor(v[i+j*m+1],min,max);
245       x3 = x2;     y3 = y[j+1]; c3 = PetscDrawRealToColor(v[i+j*m+1+m],min,max);
246       x4 = x1;     y4 = y3;     c4 = PetscDrawRealToColor(v[i+j*m+m],min,max);
247 
248       ierr = PetscDrawTriangle(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);CHKERRQ(ierr);
249       ierr = PetscDrawTriangle(draw,x1,y_1,x3,y3,x4,y4,c1,c3,c4);CHKERRQ(ierr);
250     }
251   }
252   PetscFunctionReturn(0);
253 }
254