[FIXED] redrawing snapshots - anyway to not clear them each frame? or to partially clear with alpha?

Solar2D Advanced Graphics
#1

i’m interested in a varation on this sort of thing…

http://www.youtube.com/watch?v=9dsAgCqPBWI

for a set of moving objects, rather than use a double buffered approach for a trail effect we could achieve this effect by

  1. not clearing the snapshot each frame, but multiplying a black rectangle with limited alpha over the top of the previous render before redrawing the objects. like this

http://teaching.ericforman.com/simple-object-trails-in-processing/

( the second example)

this way, the prior frame will fade slightly on each redraw. leaving the trail effect.

  1. some way of partially clearing the frame - eg, a glFillColor with < 255 alpha

is this possible in gfx2.0?

#2

Actually, we just added a new snapshot.canvas feature:

http://docs.coronalabs.com/tachyon/api/type/SnapshotObject/index.html

I’ve attached a TrailingPaint sample that shows how to achieve the effect you are looking for. Just click and drag the mouse around the screen to see the effect!

#3

perfect timing! thanks!

#4

Actually, we just added a new snapshot.canvas feature:

http://docs.coronalabs.com/tachyon/api/type/SnapshotObject/index.html

I’ve attached a TrailingPaint sample that shows how to achieve the effect you are looking for. Just click and drag the mouse around the screen to see the effect!

#5

perfect timing! thanks!

#6

Hi Walter,

was there ever a solution to the graphics not fully fading to black? this is a duplicate of the issue here

https://forums.coronalabs.com/topic/42077-snapshot-painting-trails-never-quite-fade-out/

thanks

j

mmsdtu.png

#7

Hi Walter,

was there ever a solution to the graphics not fully fading to black? this is a duplicate of the issue here

https://forums.coronalabs.com/topic/42077-snapshot-painting-trails-never-quite-fade-out/

thanks

j

mmsdtu.png