1 2 #include <petscdraw.h> /*I "petscdraw.h" I*/ 3 4 #undef __FUNCT__ 5 #define __FUNCT__ "PetscDrawZoom" 6 /*@C 7 PetscDrawZoom - Allows one to create a graphic that users may zoom into. 8 9 Collective on PetscDraw 10 11 Input Parameters: 12 + draw - the window where the graph will be made. 13 . func - users function that draws the graphic 14 - ctx - pointer to any user required data 15 16 Level: advanced 17 18 Concepts: graphics^zooming 19 Concepts: drawing^zooming 20 Concepts: zooming^in graphics 21 22 .seealso: 23 @*/ 24 PetscErrorCode PetscDrawZoom(PetscDraw draw,PetscErrorCode (*func)(PetscDraw,void*),void *ctx) 25 { 26 PetscErrorCode ierr; 27 PetscDrawButton button; 28 PetscReal dpause,xc,yc,scale = 1.0,w,h,xr,xl,yr,yl,xmin,xmax,ymin,ymax; 29 PetscBool isnull; 30 31 PetscFunctionBegin; 32 ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); 33 if (isnull) PetscFunctionReturn(0); 34 35 ierr = PetscDrawCheckResizedWindow(draw);CHKERRQ(ierr); 36 ierr = PetscDrawClear(draw);CHKERRQ(ierr); 37 ierr = PetscDrawCollectiveBegin(draw);CHKERRQ(ierr); 38 ierr = (*func)(draw,ctx);CHKERRQ(ierr); 39 ierr = PetscDrawCollectiveEnd(draw);CHKERRQ(ierr); 40 ierr = PetscDrawFlush(draw);CHKERRQ(ierr); 41 42 ierr = PetscDrawGetPause(draw,&dpause);CHKERRQ(ierr); 43 if (dpause >= 0) { 44 ierr = PetscSleep(dpause);CHKERRQ(ierr); 45 goto theend; 46 } 47 if (dpause != -1) goto theend; 48 49 ierr = PetscDrawGetMouseButton(draw,&button,&xc,&yc,NULL,NULL);CHKERRQ(ierr); 50 ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr); 51 xmin = xl; xmax = xr; w = xr - xl; 52 ymin = yl; ymax = yr; h = yr - yl; 53 54 while (button != PETSC_BUTTON_NONE && button != PETSC_BUTTON_RIGHT) { 55 switch (button) { 56 case PETSC_BUTTON_LEFT: scale = 0.5; break; 57 case PETSC_BUTTON_CENTER: scale = 2.0; break; 58 case PETSC_BUTTON_WHEEL_UP: scale = 8/10.; break; 59 case PETSC_BUTTON_WHEEL_DOWN: scale = 10/8.; break; 60 default: scale = 1.0; 61 } 62 xl = scale*(xl + w - xc) + xc - w*scale; 63 xr = scale*(xr - w - xc) + xc + w*scale; 64 yl = scale*(yl + h - yc) + yc - h*scale; 65 yr = scale*(yr - h - yc) + yc + h*scale; 66 w *= scale; h *= scale; 67 ierr = PetscDrawClear(draw);CHKERRQ(ierr); 68 ierr = PetscDrawSetCoordinates(draw,xl,yl,xr,yr);CHKERRQ(ierr); 69 ierr = PetscDrawCollectiveBegin(draw);CHKERRQ(ierr); 70 ierr = (*func)(draw,ctx);CHKERRQ(ierr); 71 ierr = PetscDrawCollectiveEnd(draw);CHKERRQ(ierr); 72 ierr = PetscDrawFlush(draw);CHKERRQ(ierr); 73 ierr = PetscDrawGetMouseButton(draw,&button,&xc,&yc,NULL,NULL);CHKERRQ(ierr); 74 } 75 ierr = PetscDrawSetCoordinates(draw,xmin,ymin,xmax,ymax);CHKERRQ(ierr); 76 theend: 77 PetscFunctionReturn(0); 78 } 79 80