Re: [Bug-freedink] Screen or Sprites Flickering

[beuc]

Hi Eric,

On Mon, Mar 13, 2017 at 07:34:24AM -0700, Eric Duhamel wrote:
> On March 12, 2017 6:33:53 AM PDT, address@hidden wrote:
> >
> >I doubt I can do much about it in FreeDink itself.  The game engine
> >relies on the SDL library to handle graphics access.
> >
> >I would suggest trying the latest development version of FreeDink,
> >which uses SDL2, which itself had specific improvements to work on
> >Raspberry Pi.
> >
> 
> I'm sorry to report I just tried a recent build of Freedink 1.08 that I 
> compiled myself from upstream source a while back, and the flicker is 
> identical. 
> 
> The flickering occurs in a band accross the width of the screen and the area 
> of effect oscillates vertically. It also migrates downward overall until it 
> gets near the bottom and starts off again near the top, affecting maybe 1/4 
> or 1/5 of the screen at a time. It does not effect most parts of the 
> background --grass, most rocks, dirt, blood spatter, pig feed--, but it does 
> effect all charactes, fencing, tall grass patches, some rocks.
> 
> I should rebuild Freedink to make absolutely sure it is from upstream and 
> using SDL2, but I feel fairly certain this is it.
> 
> P.S. I've been running other SDL-based games in framebuffer that don't 
> exhibit such a graphical glitch.

Would "tearing" (https://en.wikipedia.org/wiki/Screen_tearing)
appropriately qualify this issue?

This may happen when SDL is requesting a hardware-accelerated buffer,
but the graphics backend mistakenly updates the graphics video while
it's being redrawn.


I'm puzzled that other SDL games are running fine under the same
setup.  Maybe they are using SDL+OpenGL (rather than plain SDL), or
maybe they are not requesting hardware-accelerated 2D surfaces...

I have a RPI 1 lying around so if you give me instructions on how to
reproduce your setup I may have a look.


Recent FreeDink (SDL2) versions advertise as 1.09 (in the title bar
and in --version output, though it's still 1.08 in the in-game title
screen) so make sure the version you tried is 1.09.

Cheers!
Sylvain