Gdi on gauges

[Guest whitedragon]

Hi all,i need to use GDI functions on a gauge, but i'm not able to get a valid hdc (Handle Device Context). Please someone is able to suggest me some method to get that? I'm using VC++ 6Thanks in advance,WD

[n4gix 4,947]

It would help if you post the relevant parts of your code, so we can see what you've tried?Did you remember to include a MAKE STATIC element creating a DIBSECTION?What is your context for creating an hdc?Here's a working example:void FSAPI PFDCallBack ( PGAUGEHDR pgauge, SINT32 service_id, UINT32 extra_data ){ if(!init) { GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL); init = true; } switch (service_id) { case PANEL_SERVICE_PRE_DRAW: { PELEMENT_STATIC_IMAGE pelement = (PELEMENT_STATIC_IMAGE)(pgauge->elements_list[0]->next_element[0]); if (pelement) { HDC hdc = pelement->hdc; PIXPOINT dim = pelement->image_data.final->dim; if (hdc) { Graphics graphics(hdc);

[Guest whitedragon]

I didn't create a DIBSECTION.Following your examples, now i write this piece of code:char tmp[1024];void FSAPI test ( PGAUGEHDR pgauge, SINT32 service_id,UINT32 extra_data ){ switch (service_id) { case PANEL_SERVICE_PRE_DRAW: PELEMENT_STATIC_IMAGE pelement = NULL; strcpy(tmp, "..."); if(pgauge) { strcpy(tmp, "pgauge"); if(pgauge->elements_list[0]) { strcpy(tmp, "list[0]"); if(pgauge->elements_list[0]->next_element[0]) { strcpy(tmp, "element[0]"); PELEMENT_STATIC_IMAGE pelement = (PELEMENT_STATIC_IMAGE)(pgauge->elements_list[0]->next_element[0]); if(pelement->hdc) { strcpy(tmp, "hdc"); } } } } break; }}FLOAT64 FSAPI temperature_string_cb2( PELEMENT_STRING pelement ) { FLOAT64 val = pelement->source_var[2].var_value.n; sprintf(pelement->string, "%s", tmp); return val; }MAKE_STRING( temperature_string, NULL, NULL, IMAGE_USE_ERASE | IMAGE_USE_BRIGHT | IMAGE_USE_TRANSPARENCY, 0, 28, 9, 120, 60, 10, FUEL_QUANTITY_LEFT, FUEL_QUANTITY_RIGHT, TOTAL_FUEL_QUANTITY_GALLONS, RGB(255,0,0), RGB(0,0,0), RGB(92,92,92), GAUGE_FONT_DEFAULT, GAUGE_WEIGHT_DEFAULT, GAUGE_CHARSET, 0, DT_CENTER | DT_VCENTER | DT_SINGLELINE, NULL, temperature_string_cb2)MAKE_STATIC( temperature_background, BMP_TEMPERATURE_SMALL_BACKGROUND, &temperature_icon_list, NULL, IMAGE_USE_ERASE|IMAGE_USE_BRIGHT|IMAGE_CREATE_DIBSECTION, 0, 0,0)PELEMENT_HEADER temperature_icon_list[] ={ &temperature_string.header, NULL};PELEMENT_HEADER temperature_list= &temperature_background.header;The value of tmp string (used for debug purpose) is "element[0]", so it seems that pgauge->elements_list[0]->next_element[0] is setted but pelement->hdc is not. Do you have any suggestion?Also, i've done another test: i've replace the string callback functions with the following:FLOAT64 FSAPI temperature_string_cb2( PELEMENT_STRING pelement ) { FLOAT64 val = pelement->source_var[2].var_value.n; if(pelement->hdc) { sprintf(pelement->string, "OK", 5.3); TextOut(pelement->hdc, 0, 0, "TEST13); } else { sprintf(pelement->string, "NO", 5.3); } return val; }This time the output is "OK", making me think that here i've a hdc, but my TextOut output is overwrite after exit the function. If it's true, what do you think about save that hdc in a global variable and use it in the main callback function? There is something like PANEL_SERVICE_PRE_DRAW but POST at the place of PRE?Thank you for your helping,White Dragon

[n4gix 4,947]

Did you remember to issue a SET_OFF_SCREEN at the end of the drawing cycle? This is needed to redraw the gauge each cycle.if (pelement) { HDC hdc = pelement->hdc; PIXPOINT dim = pelement->image_data.final->dim; if (hdc) { Graphics graphics(hdc); } SET_OFF_SCREEN (pelement); } } break;Also, why use the MAKE_STRING macro? Why not simply write the string with your GDI+ code?SolidBrush whiteBrush(Color(255, 255, 255, 255));FontFamily Arial(L"Arial");Font TempTitles(&Arial, 18*dim.y, FontStyleBold, UnitPixel);PointF pointF(5.0*dim.x, 5.0*dim.y);graphics.DrawString(L"MKR", -1, &TempTitles, pointF, &whiteBrush);

[Guest whitedragon]

>Did you remember to issue a SET_OFF_SCREEN at the end of the>drawing cycle? This is needed to redraw the gauge each>cycle.I've tried just now, but nothing has changed...>Also, why use the MAKE_STRING macro? Why not simply write the>string with your GDI+ code?>>SolidBrush whiteBrush(Color(255, 255, 255, 255));>>FontFamily Arial(L"Arial");>Font TempTitles(&Arial, 18*dim.y, FontStyleBold, UnitPixel);>PointF pointF(5.0*dim.x, 5.0*dim.y);>graphics.DrawString(L"MKR", -1, &TempTitles, pointF,>&whiteBrush);I would make it if i had a valid hdc. My real problem is that i don't have any reference to the drawing area, so i must use the MS macro :( Any soluction?

[n4gix 4,947]

>I would make it if i had a valid hdc. My real problem is that>i don't have any reference to the drawing area, so i must use>the MS macro :( Any soluction?Yes. Before you can proceed, you first need to get the hdc working...Write to me at n4gix@comcast.net and I will send you a working example to get you started off on the right foot... ;)