xref: /petsc/src/sys/classes/draw/interface/dtri.c (revision 8fd105b637c659b5723a6c3ba83a32bc84aa12fb)
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 .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 {
23   PetscFunctionBegin;
24   PetscValidHeaderSpecific(draw,PETSC_DRAW_CLASSID,1);
25   PetscUseTypeMethod(draw,triangle ,x1,y_1,x2,y2,x3,y3,c1,c2,c3);
26   PetscFunctionReturn(0);
27 }
28 
29 /*@
30    PetscDrawScalePopup - draws a contour scale window.
31 
32    Collective on PetscDraw
33 
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
38 
39    Level: intermediate
40 
41    Notes:
42     All processors that share the draw MUST call this routine
43 
44 .seealso: `PetscDrawGetPopup()`, `PetscDrawTensorContour()`
45 
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];
54 
55   PetscFunctionBegin;
56   if (!popup) PetscFunctionReturn(0);
57   PetscValidHeaderSpecific(popup,PETSC_DRAW_CLASSID,1);
58   PetscCall(PetscDrawIsNull(popup,&isnull));
59   if (isnull) PetscFunctionReturn(0);
60   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)popup),&rank));
61 
62   PetscCall(PetscDrawCheckResizedWindow(popup));
63   PetscCall(PetscDrawClear(popup));
64   PetscCall(PetscDrawSetTitle(popup,"Contour Scale"));
65   PetscCall(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       PetscCall(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       PetscCall(PetscSNPrintf(string,sizeof(string),"%18.16e",(double)value));
78       PetscCall(PetscDrawString(popup,0.2,0.02+i/10.0,PETSC_DRAW_BLACK,string));
79     }
80   }
81   PetscDrawCollectiveEnd(popup);
82   PetscCall(PetscDrawFlush(popup));
83   PetscCall(PetscDrawSave(popup));
84   PetscFunctionReturn(0);
85 }
86 
87 typedef struct {
88   int       m,n;
89   PetscReal *x,*y,min,max,*v;
90   PetscBool showgrid;
91 } ZoomCtx;
92 
93 static PetscErrorCode PetscDrawTensorContour_Zoom(PetscDraw win,void *dctx)
94 {
95   int            i;
96   ZoomCtx        *ctx = (ZoomCtx*)dctx;
97 
98   PetscFunctionBegin;
99   PetscCall(PetscDrawTensorContourPatch(win,ctx->m,ctx->n,ctx->x,ctx->y,ctx->min,ctx->max,ctx->v));
100   if (ctx->showgrid) {
101     for (i=0; i<ctx->m; i++) {
102       PetscCall(PetscDrawLine(win,ctx->x[i],ctx->y[0],ctx->x[i],ctx->y[ctx->n-1],PETSC_DRAW_BLACK));
103     }
104     for (i=0; i<ctx->n; i++) {
105       PetscCall(PetscDrawLine(win,ctx->x[0],ctx->y[i],ctx->x[ctx->m-1],ctx->y[i],PETSC_DRAW_BLACK));
106     }
107   }
108   PetscFunctionReturn(0);
109 }
110 
111 /*@C
112    PetscDrawTensorContour - PetscDraws a contour plot for a two-dimensional array
113    that is stored as a PETSc vector.
114 
115    Collective on PetscDraw, but PetscDraw must be sequential
116 
117    Input Parameters:
118 +   draw  - the draw context
119 .   m,n   - the global number of mesh points in the x and y directions
120 .   xi,yi - the locations of the global mesh points (optional, use NULL
121             to indicate uniform spacing on [0,1])
122 -   V     - the values
123 
124    Options Database Keys:
125 +  -draw_x_shared_colormap - Indicates use of private colormap
126 -  -draw_contour_grid - PetscDraws grid contour
127 
128    Level: intermediate
129 
130 .seealso: `PetscDrawTensorContourPatch()`, `PetscDrawScalePopup()`
131 
132 @*/
133 PetscErrorCode  PetscDrawTensorContour(PetscDraw draw,int m,int n,const PetscReal xi[],const PetscReal yi[],PetscReal *v)
134 {
135   int            N = m*n;
136   PetscBool      isnull;
137   PetscDraw      popup;
138   int            xin=1,yin=1,i;
139   PetscMPIInt    size;
140   PetscReal      h;
141   ZoomCtx        ctx;
142 
143   PetscFunctionBegin;
144   PetscValidHeaderSpecific(draw,PETSC_DRAW_CLASSID,1);
145   PetscCall(PetscDrawIsNull(draw,&isnull));
146   if (isnull) PetscFunctionReturn(0);
147   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)draw),&size));
148   PetscCheck(size <= 1,PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"May only be used with single processor PetscDraw");
149   PetscCheck(N > 0,PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"n %d and m %d must be positive",m,n);
150 
151   ctx.v   = v;
152   ctx.m   = m;
153   ctx.n   = n;
154   ctx.max = ctx.min = v[0];
155   for (i=0; i<N; i++) {
156     if (ctx.max < ctx.v[i]) ctx.max = ctx.v[i];
157     if (ctx.min > ctx.v[i]) ctx.min = ctx.v[i];
158   }
159   if (ctx.max - ctx.min < 1.e-7) {ctx.min -= 5.e-8; ctx.max += 5.e-8;}
160 
161   /* PetscDraw the scale window */
162   PetscCall(PetscDrawGetPopup(draw,&popup));
163   PetscCall(PetscDrawScalePopup(popup,ctx.min,ctx.max));
164 
165   ctx.showgrid = PETSC_FALSE;
166   PetscCall(PetscOptionsGetBool(((PetscObject)draw)->options,NULL,"-draw_contour_grid",&ctx.showgrid,NULL));
167 
168   /* fill up x and y coordinates */
169   if (!xi) {
170     xin      = 0;
171     PetscCall(PetscMalloc1(ctx.m,&ctx.x));
172     h        = 1.0/(ctx.m-1);
173     ctx.x[0] = 0.0;
174     for (i=1; i<ctx.m; i++) ctx.x[i] = ctx.x[i-1] + h;
175   } else ctx.x = (PetscReal*)xi;
176 
177   if (!yi) {
178     yin      = 0;
179     PetscCall(PetscMalloc1(ctx.n,&ctx.y));
180     h        = 1.0/(ctx.n-1);
181     ctx.y[0] = 0.0;
182     for (i=1; i<ctx.n; i++) ctx.y[i] = ctx.y[i-1] + h;
183   } else ctx.y = (PetscReal*)yi;
184 
185   PetscCall(PetscDrawZoom(draw,PetscDrawTensorContour_Zoom,&ctx));
186 
187   if (!xin) PetscCall(PetscFree(ctx.x));
188   if (!yin) PetscCall(PetscFree(ctx.y));
189   PetscFunctionReturn(0);
190 }
191 
192 /*@
193    PetscDrawTensorContourPatch - PetscDraws a rectangular patch of a contour plot
194    for a two-dimensional array.
195 
196    Not Collective
197 
198    Input Parameters:
199 +  draw - the draw context
200 .  m,n - the number of local mesh points in the x and y direction
201 .  x,y - the locations of the local mesh points
202 .  min,max - the minimum and maximum value in the entire contour
203 -  v - the data
204 
205    Options Database Keys:
206 .  -draw_x_shared_colormap - Activates private colormap
207 
208    Level: advanced
209 
210    Note:
211    This is a lower level support routine, usually the user will call
212    PetscDrawTensorContour().
213 
214 .seealso: `PetscDrawTensorContour()`
215 
216 @*/
217 PetscErrorCode  PetscDrawTensorContourPatch(PetscDraw draw,int m,int n,PetscReal *x,PetscReal *y,PetscReal min,PetscReal max,PetscReal *v)
218 {
219   int            c1,c2,c3,c4,i,j;
220   PetscReal      x1,x2,x3,x4,y_1,y2,y3,y4;
221 
222   PetscFunctionBegin;
223   PetscValidHeaderSpecific(draw,PETSC_DRAW_CLASSID,1);
224   /* PetscDraw the contour plot patch */
225   for (j=0; j<n-1; j++) {
226     for (i=0; i<m-1; i++) {
227       x1 = x[i];   y_1 = y[j];  c1 = PetscDrawRealToColor(v[i+j*m],min,max);
228       x2 = x[i+1]; y2 = y_1;    c2 = PetscDrawRealToColor(v[i+j*m+1],min,max);
229       x3 = x2;     y3 = y[j+1]; c3 = PetscDrawRealToColor(v[i+j*m+1+m],min,max);
230       x4 = x1;     y4 = y3;     c4 = PetscDrawRealToColor(v[i+j*m+m],min,max);
231 
232       PetscCall(PetscDrawTriangle(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3));
233       PetscCall(PetscDrawTriangle(draw,x1,y_1,x3,y3,x4,y4,c1,c3,c4));
234     }
235   }
236   PetscFunctionReturn(0);
237 }
238