Jump to content
  • Advertisement

Archived

This topic is now archived and is closed to further replies.

fredjordans

structuring a class

This topic is 6084 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

OK, I am having problems structuring my DirectX app (I am writing it in Visual Basic). I have a class that allows me to do the following: - initialise DX - create a surface - draw surface to the backbuffer - flip surfaces - shutdown dx My problem is as follows: When I draw a surface to the backbuffer, the Blit function needs a source rect to be specified. However, I don't want the user of the class to have to specify the source rect (width and height of the image) each time. I just want it to accept the surface's default width and height (as specified when calling the CreateSurface procedure). However, I don't know how this can be done, since surfaces don't seem to have a width and height property... EDIT: I guess I ultimately want to create a 'sprite' object that will hold the surface, its dimensions, and even its current x and y coordinates so that I can track its position on the screen. I want to be able to use this object to support animated sprites in the future. However, the problem with this is that I hav a seperate class used to initialize DirectX and destroy it, and since classes can't reference external variables, I don't know how, in the sprite class, I could make use of the DX and DD objects, and everything else needed to successfuly create and Blit a surface. Any suggestions? Edited by - fredjordans on February 25, 2002 9:13:31 PM

Share this post


Link to post
Share on other sites
Advertisement
Use BltFast(...)

I forgot what parameters you''re required to pass because I haven''t been doing graphics for a long time. Okay, I''m too lazy to look it up as well...

Also, you might want to add more functionality to the class:
- Load Bitmaps to a surface
- Draw Lines, Pixels, Rects
- Alpha Blending

Also, what I do is create functions that blit for you. So I have
  
DrawToSurface(int x, int y, LPDIRECTDRAWSURFACE7 source); //<- Bare bones (Uses BltFast(...))

DrawToSurface to surface(int x, int y, LPDIRECTDRAWSURFACE7 source, LPDIRECTDRAWSURFACE7 dest);
DrawToSurfaceSourceRect(RECT source_rect, LPDIRECTDRAWSURFACE7 source, LPDIRECTDRAWSURFACE7 dest);
DrawToSurfaceTargetRect(RECT target_rect, LPDIRECTDRAWSURFACE7 source, LPDIRECTDRAWSURFACE7 dest);
DrawToSurfaceTargetRectSourceRect(RECT source_rect, RECT target_rect, LPDIRECTDRAWSURFACE7 source, LPDIRECTDRAWSURFACE7 dest);


Also, you might want to have another set of functions that draw directly on the back buffer. So you''ll have:

  
DrawSurface(int x, int y); //<- No target. Target is backbuffer

//...



Note that only the DrawSurface(...) and DrawToSurface(...) uses BltFast(...), which does not need a RECT.

Share this post


Link to post
Share on other sites

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

We are the game development community.

Whether you are an indie, hobbyist, AAA developer, or just trying to learn, GameDev.net is the place for you to learn, share, and connect with the games industry. Learn more About Us or sign up!

Sign me up!