micro@imada.dk (Klaus Pedersen) (03/04/91)
Hi, Is it possible to use VDI operations to draw on a virtual screen? Possibly on a screen which is bigger than the real screen. Now, I am drawing in a window, copying the inner to a buffer, and copying it back into the window when I get a redraw, or determining which part of the buffer is valid when I get a scroll or size, and then copy the valid part into the window, drawing the other area(s), and then copying the new contents to the buffer... - It would be easier to draw in a big buffer, and only copy the portion which is visible to the window. I think that AIM is using a virtual buffer to it's images, but I guess that it is using custom drawing functions... -Klaus
micro@imada.dk (Klaus Pedersen) (03/06/91)
micro@imada.dk (Klaus Pedersen) writes: >Is it possible to use VDI operations to draw on a virtual screen? Possibly >on a screen which is bigger than the real screen. Yes, writing on a virtual screen is easy (by setting the logical screen to your buffer - with 'Setscreen'). But is it possible to change the size of the logical screen? - Is it possible to tell the VDI about a new size (x,y,planes) ? I have a nightmare about a user with a video controller with true color at 1024x1024 (thats 3 Mbytes)!!! You need to allocate all 3 Mb before setting the logical screen!! - can this be true?? -Klaus