1 #include <petscdraw.h> /*I "petscdraw.h" I*/ 2 3 /*@C 4 PetscDrawZoom - Allows one to provide a function that gets called for zooming in on a drawing using the mouse buttons 5 6 Collective draw 7 8 Input Parameters: 9 + draw - the window where the graph will be made. 10 . func - users function that draws the graphic 11 - ctx - pointer to any user required data 12 13 Level: advanced 14 15 .seealso: `PetscDraw`, `PetscDrawCreate()` 16 @*/ 17 PetscErrorCode PetscDrawZoom(PetscDraw draw, PetscErrorCode (*func)(PetscDraw, void *), void *ctx) 18 { 19 PetscDrawButton button; 20 PetscReal dpause, xc, yc, scale = 1.0, w, h, xr, xl, yr, yl, xmin, xmax, ymin, ymax; 21 PetscBool isnull; 22 23 PetscFunctionBegin; 24 PetscCall(PetscDrawIsNull(draw, &isnull)); 25 if (isnull) PetscFunctionReturn(PETSC_SUCCESS); 26 27 PetscCall(PetscDrawCheckResizedWindow(draw)); 28 PetscCall(PetscDrawClear(draw)); 29 PetscDrawCollectiveBegin(draw); 30 PetscCall((*func)(draw, ctx)); 31 PetscDrawCollectiveEnd(draw); 32 PetscCall(PetscDrawFlush(draw)); 33 34 PetscCall(PetscDrawGetPause(draw, &dpause)); 35 if (dpause >= 0) { 36 PetscCall(PetscSleep(dpause)); 37 goto theend; 38 } 39 if (dpause != -1) goto theend; 40 41 PetscCall(PetscDrawGetMouseButton(draw, &button, &xc, &yc, NULL, NULL)); 42 PetscCall(PetscDrawGetCoordinates(draw, &xl, &yl, &xr, &yr)); 43 xmin = xl; 44 xmax = xr; 45 w = xr - xl; 46 ymin = yl; 47 ymax = yr; 48 h = yr - yl; 49 50 while (button != PETSC_BUTTON_NONE && button != PETSC_BUTTON_RIGHT) { 51 switch (button) { 52 case PETSC_BUTTON_LEFT: 53 scale = 0.5; 54 break; 55 case PETSC_BUTTON_CENTER: 56 scale = 2.0; 57 break; 58 case PETSC_BUTTON_WHEEL_UP: 59 scale = 8 / 10.; 60 break; 61 case PETSC_BUTTON_WHEEL_DOWN: 62 scale = 10 / 8.; 63 break; 64 default: 65 scale = 1.0; 66 } 67 xl = scale * (xl + w - xc) + xc - w * scale; 68 xr = scale * (xr - w - xc) + xc + w * scale; 69 yl = scale * (yl + h - yc) + yc - h * scale; 70 yr = scale * (yr - h - yc) + yc + h * scale; 71 w *= scale; 72 h *= scale; 73 PetscCall(PetscDrawClear(draw)); 74 PetscCall(PetscDrawSetCoordinates(draw, xl, yl, xr, yr)); 75 PetscDrawCollectiveBegin(draw); 76 PetscCall((*func)(draw, ctx)); 77 PetscDrawCollectiveEnd(draw); 78 PetscCall(PetscDrawFlush(draw)); 79 PetscCall(PetscDrawGetMouseButton(draw, &button, &xc, &yc, NULL, NULL)); 80 } 81 PetscCall(PetscDrawSetCoordinates(draw, xmin, ymin, xmax, ymax)); 82 theend: 83 PetscFunctionReturn(PETSC_SUCCESS); 84 } 85