Lighting a DIBSECTION...

[n4gix 4,947]

I am looking for a way to control whether a GDI+ gauge's drawing surface can be made "BRIGHT" and controllable via the panel lights switch.MAKE_STATIC( vision_image, BMP_VT_BG, NULL, NULL, IMAGE_USE_ERASE|IMAGE_USE_BRIGHT|IMAGE_CREATE_DIBSECTION, 0, MAP_LEFT_BORDER,MAP_TOP_BORDER)While this example is "lighted" via the IMAGE_USE_BRIGHT flag, there's no way to "turn it off."Does anyone have a clue how I can achieve this goal?I had thought that if I used a SLIDER for this, I could then use the callback to control the BRIGHT and DARKEN a la traditional bitmaps, but it seems that I can't use a SLIDER type with the IMAGE_CREATE_DIBSECTION flag.I suppose I should point out that I'm creating an LCD type gauge, and am using a photo of the guage as the BMP_VT_BG image, so it is important that any solution keep that in mind... ;)IOW, I'm only drawing the LCD "segments" of the gauge, NOT the "painted scales, labels and other markings..."

[Guest qsysk]

how about using 2 identical Static Images. The one should use the IMAGE_USE_BRIGHT and the other it shouldn't.MAKE_STATIC(img_var_wb,BMP_WB,NULL,NULL,IMAGE_USE_ERASE|IMAGE_USE_BRIGHT|IMAGE_CREATE_DIBSECTION,0,0,0)// Next element declaration should go here.MAKE_STATIC(img_var_wob,BMP_WOB,next_element,NULL,IMAGE_USE_ERASE|IMAGE_CREATE_DIBSECTION,0,0,0)The button should control img_var_wb by using HIDE_IMAGE and SHOW_IMAGE macros.---------------------------------------------------------------------In the other hand you can use Graphics::FillRectangle method with a black brush with variable alphaFor example: BYTE bDarkenLevel = 255; // <- This should control darkness level SolidBrush DarkenBrush(Color(bDarkenLevel,0,0,0)); Graphics G(hdc); G.FillRectangle(&DarkenBrush,...);This portion of code should be placed last in the drawing algo.

[Guest HartmannH]

No. The first way won't work. If you try to use IMAGE_CREATE_DIBSECTION without IMAGE_USE_BRIGHT, you just get a black bitmap.The best way to lighten/darken a DIB section is to put an alpha channel layer above it for brightness control like in the second example.

[n4gix 4,947]

>No. The first way won't work. If you try to use>IMAGE_CREATE_DIBSECTION without IMAGE_USE_BRIGHT, you just get>a black bitmap.>>The best way to lighten/darken a DIB section is to put an>alpha channel layer above it for brightness control like in>the second example.That would be true Hans, IF I was not using an actual "photograph" for the background image. I'm building a Vision Microsystems LCD engine cluster. The "scales" and "legends" are printed on the plastic cover for the LCD screen, and there's a nice "reflective sheen" to the plastic that I don't wish to lose... ;)Of course, that is the very reason why the second method wouldn't work for me either... ;)I solved the problem by simply creating a SLIDER and switching a copy of the background image on/off as a "cover." Further, to mask the tiny bits of the corners that overlap the bezel when the background is backlighted, I added another SLIDER with just the bezel.However, I do use method #2 for other GDI+ gauges that are wholly drawn on a blank background. It's quite effective.Doug Dawson sent me a unique solution to the question, which I'm including below just for sake of completness... ;)case PANEL_SERVICE_PRE_DRAW: lookup_var(&panel_lights); if ( lights_now != panel_lights.var_value.n ) { if ( panel_lights.var_value.n == 1 ) {bg_element->image_flags |= IMAGE_USE_BRIGHT;} else if ( panel_lights.var_value.n == 0 ) {bg_element->image_flags &= ~IMAGE_USE_BRIGHT;} REDRAW_IMAGE(bg_element); lights_now = panel_lights.var_value.n; }break;This works only to change the flag for the static. For some reason, bg_element->next_element->image_flags is not valid and will not allow the gauge to compile...http://forums.avsim.net/user_files/124232.jpg