Re: [AGG] Question about memory usage on small MCU

[Niki S. <nik...@gm...>]

On 5.07.23 г. 1:17 ч., Hugo Elias via Vector-agg-general wrote:
> I have just started trying to use AGG on a microcontroller with 264kB 
> memory. My image buffer is 240x240x3 = 172kB, and if I allow for memory 
> for other stuff, I reckon there's about 50kB of memory free for AGG to use.
> 
> However, when I try to run the simple star example, which draws a 
> 5-pointed star, I get an out-of-memory error. Adding some print 
> statements to the pod_allocator, I can see that a surprisingly large 
> amount of memory is being allocated for this simple task:
> 
> pod_allocator   512 bytes
> pod_allocator  1536 bytes
> pod_allocator   512 bytes
> pod_allocator  1024 bytes
> pod_allocator  2048 bytes
> pod_allocator 65536 bytes
> pod_allocator  3384 bytes
> pod_allocator   944 bytes
> pod_allocator  1664 bytes
> pod_allocator   104 bytes
> pod_allocator   512 bytes
> pod_allocator  1536 bytes
> pod_allocator   512 bytes
> pod_allocator  1024 bytes
> pod_allocator  9904 bytes
> 
> At one point it allocates 64kB! Just to draw a 5-pointed star. Is this 
> to be expected, or am I doing something wrong?  Is there some way to 
> make it use less memory?
> 
> double star[] = {50,  3, 20, 101, 95, 35, 5, 39, 80, 92, 50,  3};
> SimplePath path(star, sizeof(star) / sizeof(double));
> agg::conv_stroke<SimplePath> strokePath(path);
> double strokeWidth = 2.0;
> strokePath.width(strokeWidth);
> strokePath.line_cap(agg::square_cap);
> strokePath.line_join(agg::miter_join);
> strokePath.miter_limit(strokeWidth);
> ras.reset();
> ras.add_path(strokePath);
> agg::render_scanlines_aa_solid(ras, scanline, rBase, redColor);
> 

IIRC 512 is the default chink size. You can try to change it.

HTH
Niki