Drawing a large number of individual pixels per frame

Questions about the LÖVE API, installing LÖVE and other support related questions go here.
Forum rules
Before you make a thread asking for help, read this.
User avatar
kraftman
Party member
Posts: 277
Joined: Sat May 14, 2011 10:18 am

Re: Drawing a large number of individual pixels per frame

Post by kraftman »

kefka wrote:
kikito wrote:Are you generating the framebuffer on every frame, by any chance?
I am, because I'm looking for a solution where I can dynamically display the map. However I suppose what I can do is only call newPoint on the framebuffer when a tile's data changes.

Thanks for all the suggestions, I will profile this method against the ImageData method and post my results.
What changes about the map?
kefka
Prole
Posts: 9
Joined: Thu Feb 17, 2011 3:34 am

Re: Drawing a large number of individual pixels per frame

Post by kefka »

kraftman wrote:
kefka wrote:
kikito wrote:Are you generating the framebuffer on every frame, by any chance?
I am, because I'm looking for a solution where I can dynamically display the map. However I suppose what I can do is only call newPoint on the framebuffer when a tile's data changes.

Thanks for all the suggestions, I will profile this method against the ImageData method and post my results.
What changes about the map?
Good question. The map is randomly generated by a cave-digging algorithm. I'd like to provide an interface to modify parameters of the algorithm and display the generation realtime.
User avatar
kraftman
Party member
Posts: 277
Joined: Sat May 14, 2011 10:18 am

Re: Drawing a large number of individual pixels per frame

Post by kraftman »

In that case I would recommend frame buffers. Using image data, you would need to create a new image to display each time new terrain is generated, while using frame buffers you can add extra info to the same frame buffer. I haven't used spritebatches yet, but I think you could do something similar with them.
User avatar
Taehl
Dreaming in associative arrays
Posts: 1025
Joined: Mon Jan 11, 2010 5:07 am
Location: CA, USA
Contact:

Re: Drawing a large number of individual pixels per frame

Post by Taehl »

If he used the ImageData method, he could use ImageData:setPixel to add the changes to the map. He wouldn't have to re-generate the whole map every frame.

I wouldn't recommend spritebatches for this, as you WOULD need to re-generate it all the time (you can only add more and more to a spritebatch, not change or remove graphics from it).
Earliest Love2D supporter who can't Love anymore. Let me disable pixel shaders if I don't use them, dammit!
Lenovo Thinkpad X60 Tablet, built like a tank. But not fancy enough for Love2D 0.10.0+.
User avatar
slime
Solid Snayke
Posts: 3166
Joined: Mon Aug 23, 2010 6:45 am
Location: Nova Scotia, Canada
Contact:

Re: Drawing a large number of individual pixels per frame

Post by slime »

Taehl wrote:If he used the ImageData method, he could use ImageData:setPixel to add the changes to the map. He wouldn't have to re-generate the whole map every frame.

I wouldn't recommend spritebatches for this, as you WOULD need to re-generate it all the time (you can only add more and more to a spritebatch, not change or remove graphics from it).
You do have to call love.graphics.newImage(imagedata) every time you change it, which creates a whole new image from the imagedata. This will create huge amounts of RAM if you aren't careful, AFAIK.

Regenerating spritebatches is generally pretty efficient, comparatively. Doing a streaming spritebatch (re-creating every frame) can be faster than drawing each image individually, and an infrequently-updated (less than once per frame) spritebatch is pretty much always faster than drawing individual images.
User avatar
T-Bone
Inner party member
Posts: 1492
Joined: Thu Jun 09, 2011 9:03 am

Re: Drawing a large number of individual pixels per frame

Post by T-Bone »

slime wrote:
Taehl wrote:If he used the ImageData method, he could use ImageData:setPixel to add the changes to the map. He wouldn't have to re-generate the whole map every frame.

I wouldn't recommend spritebatches for this, as you WOULD need to re-generate it all the time (you can only add more and more to a spritebatch, not change or remove graphics from it).
You do have to call love.graphics.newImage(imagedata) every time you change it, which creates a whole new image from the imagedata. This will create huge amounts of RAM if you aren't careful, AFAIK.

Regenerating spritebatches is generally pretty efficient, comparatively. Doing a streaming spritebatch (re-creating every frame) can be faster than drawing each image individually, and an infrequently-updated (less than once per frame) spritebatch is pretty much always faster than drawing individual images.
Well, it shouldn't be using all that much RAM unless you're storing all the images. It will make the garbage collector go nuts, though, which is never a good thing. I'm not sure how good the GC is in Lua (if it were Android, it would've made the app unusable (although I think they improved the GC in Android 2.3)) :neko:
User avatar
Taehl
Dreaming in associative arrays
Posts: 1025
Joined: Mon Jan 11, 2010 5:07 am
Location: CA, USA
Contact:

Re: Drawing a large number of individual pixels per frame

Post by Taehl »

slime wrote:This will create huge amounts of RAM if you aren't careful, AFAIK.
I did a test, setting a pixel / newImage-ing / drawing a 256x256 image at about a thousand times per second, and didn't see Love's RAM usage go over 26 megs.
Earliest Love2D supporter who can't Love anymore. Let me disable pixel shaders if I don't use them, dammit!
Lenovo Thinkpad X60 Tablet, built like a tank. But not fancy enough for Love2D 0.10.0+.
User avatar
kraftman
Party member
Posts: 277
Joined: Sat May 14, 2011 10:18 am

Re: Drawing a large number of individual pixels per frame

Post by kraftman »

It's still less efficient to create a new image each time than to just add the extra data to the same framebuffer
User avatar
benloran
Prole
Posts: 19
Joined: Tue Jul 05, 2011 4:52 pm

Re: Drawing a large number of individual pixels per frame

Post by benloran »

kraftman wrote:It's still less efficient to create a new image each time than to just add the extra data to the same framebuffer
Unless I'm misunderstanding you, I don't think you can do this in Love 0.7.2, since framebuffers are cleared automatically each time you draw to them. (Though I believe this is fixed in 0.8.0).
User avatar
adrix89
Party member
Posts: 135
Joined: Fri Oct 15, 2010 10:58 am

Re: Drawing a large number of individual pixels per frame

Post by adrix89 »

What about the Sonic solution?
Tile with hightmap info?
I use Workflowy but you can check out Dynalist as its the better offer.
Post Reply

Who is online

Users browsing this forum: Amazon [Bot] and 5 guests