1 2 #include <petscdraw.h> /*I "petscdraw.h" I*/ 3 4 /*@C 5 PetscDrawZoom - Allows one to create a graphic that users may zoom into. 6 7 Collective on PetscDraw 8 9 Input Parameters: 10 + draw - the window where the graph will be made. 11 . func - users function that draws the graphic 12 - ctx - pointer to any user required data 13 14 Level: advanced 15 16 .seealso: 17 @*/ 18 PetscErrorCode PetscDrawZoom(PetscDraw draw, PetscErrorCode (*func)(PetscDraw, void *), void *ctx) { 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(0); 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: scale = 0.5; break; 53 case PETSC_BUTTON_CENTER: scale = 2.0; break; 54 case PETSC_BUTTON_WHEEL_UP: scale = 8 / 10.; break; 55 case PETSC_BUTTON_WHEEL_DOWN: scale = 10 / 8.; break; 56 default: scale = 1.0; 57 } 58 xl = scale * (xl + w - xc) + xc - w * scale; 59 xr = scale * (xr - w - xc) + xc + w * scale; 60 yl = scale * (yl + h - yc) + yc - h * scale; 61 yr = scale * (yr - h - yc) + yc + h * scale; 62 w *= scale; 63 h *= scale; 64 PetscCall(PetscDrawClear(draw)); 65 PetscCall(PetscDrawSetCoordinates(draw, xl, yl, xr, yr)); 66 PetscDrawCollectiveBegin(draw); 67 PetscCall((*func)(draw, ctx)); 68 PetscDrawCollectiveEnd(draw); 69 PetscCall(PetscDrawFlush(draw)); 70 PetscCall(PetscDrawGetMouseButton(draw, &button, &xc, &yc, NULL, NULL)); 71 } 72 PetscCall(PetscDrawSetCoordinates(draw, xmin, ymin, xmax, ymax)); 73 theend: 74 PetscFunctionReturn(0); 75 } 76