Thoughts on why you are seeing slowdown: 1) Perhaps you don't have save/restore state implemented correctly and the OS is starting a second instance of your game when you switch perspectives? (the 2 running at once theory)
2) Perhaps you are drawing more somehow in landscape? 3) Perhaps you are resizing a portrait background into landscape every frame? (This is the one I'd look at first. Make sure you are drawing bitmaps 1-to-1 and not stretching or resizing every frame. If you are going to need to rotate, resize, etc use a Transform, but make sure not to do anything computationally intensive frame-by-frame unless you have to - EG if you need to scale your background to fit the new orientation, do that _once_ onto a new canvas/bitmap and redraw that bitmap onto the surface. On Oct 20, 10:43 am, mscwd01 <[EMAIL PROTECTED]> wrote: > Thanks for the update... > > I believe I am using a SurfaceView, I edited the LunarLander game > which has things like SurfaceHolders I am making use of. I use a > simple Canvas and draw onto it in much the same way you described, > i.e. base images first then draw another image on top. I was just > wondering whether Android had a layer manager much like J2ME does in > the GameCanvas class. > > Anyway thanks for your help, I believe I can implement the game now. > > Oh, one last question - why does my game run faster when the emulator > is in a portrait orientation? When I switch to landscape the game > slows by at least 20 FPS. Is this normal? > > Thanks > > On Oct 20, 3:55 pm, Robert Green <[EMAIL PROTECTED]> wrote: > > > Something like that. Play around with it and I'm sure you'll find a > > way to make it work. > > > Here's how I do mine: > > > When initializing the game/map, I load the map resource and draw it > > onto a bitmap. > > > My Main Loop: > > > update() > > draw() > > > My update method does: > > > updatePhysics (moves players, checks collisions) > > updateAI (figures out next move for AI players) > > updateState (for state transitions) > > updateAnimations > > updateSound > > > My draw method does: > > > draws background/map bitmap to surface canvas > > draws objects or anything under the players to canvas > > draws players to surface canvas > > draws FX, explosions, etc over players to surface canvas > > draws scores, text or anything on the very top to surface canvas > > > I've been very careful to write efficient math for physics, AI and > > collisions. I also was careful so as to draw the absolute minimum as > > 2d drawing is a little expensive in android. Overall I get a > > framerate around 40-45 FPS on my emulator. > > > Also - if you're not already, use a SurfaceView. > > > On Oct 19, 6:37 pm, mscwd01 <[EMAIL PROTECTED]> wrote: > > > > Thanks for your reply, > > > > So just to recap... > > > I draw the main maze png background image and then have another image > > > I draw on top of this which is fully transparent apart from lines of > > > non transparent pixels which represent the maze walls. That sounds > > > nice and easy. > > > > To make this work I'd need to find out the center point (coordinates) > > > of the screen, determine which coordinates the playing piece current > > > fills (i.e. y,x,y+10,x+10) and then check to see whether any of these > > > pixels are also occupied by the mask "walls" layer. > > > > Could you let me know the best way to implement multiples layers, i.e. > > > the maze background image, the mask walls image and the playing piece. > > > > Also could you let me know how you retrieve a section of pixels from > > > an image, so I can determine whether the mask layer for example has > > > walls in a section occupied by the playing piece. > > > > Many thanks! > > > > On Oct 19, 10:38 pm, Robert Green <[EMAIL PROTECTED]> wrote: > > > > > How did you express your walls programmatically? Did you use tiles or > > > > did you draw lines? > > > > > If you used tiles, the collision detection is very easy. If the next > > > > move will cause the player to enter the tile, game over. > > > > > If you drew the walls on a full coordinate system, you have to keep > > > > the coordinates that you used in an array or list or wherever and > > > > write a little algorithm that checks to see if the position of the > > > > player on the next tick will intersect with a wall. > > > > > I used the second method for my game and it works very well. > > > > > I just wrote all this then reread and saw that you used a png > > > > background. Here's what you can do to use that: > > > > > Create a second background that is only black and white and masks the > > > > png background you have. Load both but of course only draw your > > > > normal one. Load the mask into a bitmap and for collision detection, > > > > just call bitmap.getPixel() for the next position of your player. If > > > > it's the wall color (let's say you use white for walls), there is a > > > > collision. > > > > > On Oct 19, 5:51 am, mscwd01 <[EMAIL PROTECTED]> wrote: > > > > > > I am fairly new to android, although I have been using Java for a > > > > > while. > > > > > > I am creating a 2d maze based game which consists of a bunch of walls > > > > > and a rotating player piece (which rotates 360 degrees), while trying > > > > > to get from the entrance to the exit of the maze - without touching > > > > > the walls. > > > > > > My question is, what is the best way to represent the walls of the > > > > > maze and the playing piece (which rotates, hence doesn't always occupy > > > > > the same location on screen) so that I can effectively check for > > > > > collisions between the two entities? > > > > > > The level itself will be quite small so the maze will be a png > > > > > background image which moves when the player moves up, down, left or > > > > > right (the playing piece will remain at the center of the screen). I > > > > > was thinking of drawing a polygon object over the walls of the png > > > > > image and try to detect collisions between the rectangle playing piece > > > > > and the polygon shape - is this possible? > > > > > > There may be a better way, if there is please let me know! > > > > > > Thanks- Hide quoted text - > > > > > - Show quoted text - > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
