Strange Behaviour On Screen
Blitz3D Forums/Blitz3D Programming/Strange Behaviour On Screen
| ||
| Hi, I'm using 3D to create a 2D game. Using meshes. The map width is 8192 by 8192 of which I display 1024 by 768 pixels on screen. Works fine until I force Antialiasing on which makes things go mental. I will be drawing 'spans' of the full width i.e. 8192 'clipped' to 1024 on screen using a mesh to store the lines. Is it a graphics card limitation? I don't know. Are all cards the same? Any help appreciated Jim |
| ||
| I can't really get a handle on what you're experiencing from your description. Can you post a screenshot? |
| ||
| Imagine the original thrust landscape, so wide by so high. Rather than using sprites I use a mesh to store each horizontal line segment for the landscape. Then all I need to do is move the mesh to emulate scrolling. Works fine with AA off but goes all wrong with it on. All segments are at integer values, so I think AA must use floats in the Graphics card and overflow or something. That's my guess. Jim |
| ||
| It's very hard to understand what "but goes all wrong" means. I mean there are many different kinds of all wrong ( and God knows, I've caused most of them ) so it's hard to know exactly what the problem might be. Apart from "Can I see a screenshot please?" I guess the question becomes why are you drawing exclusively at integer coordinates? 3D is always floating point and if you want it to scroll ( and zoom? ) smoothly then you'll have to have everything as floating point. |
| ||
Sorry, here are screens.  I just scroll by 1 pixel at a time hence integer starts & ends. Thanks Jim |
| ||
| Holy cow, when you said lines, I thought you meant hollow shapes. Isn't it horribly slow drawing all those lines? Wouldn't it be easier to create one mesh for the whole shape instead of one per line? Perhaps there's more going on here than meets the eye, so perhaps that's not possible. I would give it a go with floating point coordinates and see if that does the trick. |
| ||
| That's got to be a GFX driver issue. I very much doubt blitz is to blame for this, just by switching AA on/off. |
| ||
| Is the graphics card struggling to keep up with the AA activated - I mean what kind of hit on FPS is this giving? |
| ||
| The graphics card IS doing the AA. |
| ||
| Yeh, but it might be struggling. He may have a puny little Matrox Mystique card or something. |
| ||
| Those images are AMAZING!!! I mean, it's almost like a freak coincidence piece of cumpter-generated art!!! WOW!!!!! (What can I say; I love art deco! :P ) |
| ||
| Gabriel, if you look close you will see I'm only drawing every 2nd line. Hence using 'lines'. I actually have 32 meshes per level. I have a Radeon 9800Pro card, old but good enough for this. I'll see if there is a newer driver. [edit] Where do I get them for WinXP Home? Thanks Jim |
| ||
| Card manufacturer's website? |
| ||
| OK I have tried the new drivers and it still happens. Click here! If someone could try it on their computer it would be appreciated. With & Without AA. Use the arrow keys to move around. Thanks Jim |
| ||
| Well, AA doesn't work on my PC with blitz anyway, but that demo displays fine. How do you turn AA on/off, though? Nice Thrust engine you got there, BTW. ;) |
| ||
| Hi big10p, I turn it on/off at the graphics card via the little 'ATI' icon. It doesnot work through B3D. The engine is quite fast, on my machine it does the drawing in under a millisec. Thanks Jim |
| ||
| Looks fine but seems to flash like crazy - probably something to do with how close the lines are and my guff gfx440 card. |
| ||
| Heh - it was fine on my GF2. :P |
| ||
| Stevie, any chance of a screenie? How much VRAM? 32 should be plenty. |
| ||
| 64meg VRAM. It only flashes when I move so a screenshot probably won't show much. |
   |