Hey I'm looking for a simple way to draw a filled shape that isn't one of the standard shapes. For example, a pizza slice or a large triangle.

Any suggestions? I can draw the outline okay but I want it filled.

You're gonna want a "trifill" function, there isn't one included with Pico8. There have been a few floating around the forums here, the first one that comes to mind is part of electric gryphon's 3D engine library.

There's a function in there called solid_trifill(). It shouldn't be too hard to extract that from the code if you just want to use that by itself...

https://www.lexaloffle.com/bbs/?tid=28077

That function in itself can only draw a triangle, to construct anything more complex you'd have to call it multiple times, piecing the shape together from triangles.

EDIT: Or there's the post below!!

Here's my polyfill code:

-- draws a filled convex polygon -- v is an array of vertices -- {x1, y1, x2, y2} etc function render_poly(v,col) col=col or 5 -- initialize scan extents -- with ludicrous values local x1,x2={},{} for y=0,127 do x1[y],x2[y]=128,-1 end local y1,y2=128,-1 -- scan convert each pair -- of vertices for i=1, #v/2 do local next=i+1 if (next>#v/2) next=1 -- alias verts from array local vx1=flr(v[i*2-1]) local vy1=flr(v[i*2]) local vx2=flr(v[next*2-1]) local vy2=flr(v[next*2]) if vy1>vy2 then -- swap verts local tempx,tempy=vx1,vy1 vx1,vy1=vx2,vy2 vx2,vy2=tempx,tempy end -- skip horizontal edges and -- offscreen polys if vy1~=vy2 and vy1<128 and vy2>=0 then -- clip edge to screen bounds if vy1<0 then vx1=(0-vy1)*(vx2-vx1)/(vy2-vy1)+vx1 vy1=0 end if vy2>127 then vx2=(127-vy1)*(vx2-vx1)/(vy2-vy1)+vx1 vy2=127 end -- iterate horizontal scans for y=vy1,vy2 do if (y<y1) y1=y if (y>y2) y2=y -- calculate the x coord for -- this y coord using math! x=(y-vy1)*(vx2-vx1)/(vy2-vy1)+vx1 if (x<x1[y]) x1[y]=x if (x>x2[y]) x2[y]=x end end end -- render scans for y=y1,y2 do local sx1=flr(max(0,x1[y])) local sx2=flr(min(127,x2[y])) local c=col*16+col local ofs1=flr((sx1+1)/2) local ofs2=flr((sx2+1)/2) memset(0x6000+(y*64)+ofs1,c,ofs2-ofs1) pset(sx1,y,c) pset(sx2,y,c) end end |

Here's a little doodle using your triangle code. Thanks for sharing =)

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