Pixel art balls (spheres or marbles etc.) 
 featuring advanced techniques in 2 bits: 
 dithering, antialiasing, masks/outlines. 
 Size: 24x24 (=3x3 blocks of 8x8 pixels). 

 Neat spheres challenge the pixel artist. 


Top row, full list of cumulative changes: 
#1: common/flawed ball design [original]; 
#2: removed some noise (isolated pixels); 
#3: fixed the outline (aliasing and gap); 
#4: fixed the reflection (aliasing only); 
#5: removed outer half of this dithering; 
#6: removed inner half of this dithering; 
#7: corrected the outer and focal lights; 
#8: added inner dithering (strict order); 
#9: added outer dithering (strict order); 
#10: added extra outer dithering (ditto); 
#11: corrected the strict order (dither); 
#12: degraded both reflections (dithers); 
#13: added a few glints (dithered there); 
#14: fine-tuned/contrasted glows [final]. 

Bottom row, animated as Gif if available, 
featuring two kinds of outlines as masks: 
simulated gray on left (ani. white dots); 
plain white on right (static & portable). 
These couples help cut any B/W background 
(B+W & W+B are complementary approaches). 
The standard method is seen on the right; 
the advanced method I suggest on the left 
employs 104 frames here (via 8x8 blocks). 
A simple white ouline is solid & aliased; 
this tricky one is dotted, even embedded, 
as in a box selection in a bitmap editor. 

The rows test the contrasts, even the AA, 
in pairs (from row 2 till B): without and 
with external outline (even and odd rows) 
- the last column shows a few tweaks, and 
the color of this outline varies greatly. 
This fairly features a set of mixed masks 
that can alleviate B/W background issues. 
The antialiased and dithered outlines are 
advanced pixel art and design techniques, 
when dealing typically with 1-bit images. 
The row C (black BG) is 1-bit and a half, 
i.e. including the gray external outline. 

Various sphere textures build the columns 
(top row excepted, see the how-to above): 
#1 till 13 got tricky oulines, unlike 14. 
They feature several concepts and styles: 
varying glass effects (specular, envir.); 
varying thicknesses in the black outline; 
varying dithering techniques (hard ones); 
varying dot scattering, even gray colors; 
while the lighting remains the same (NW). 
The cast shadows can quite fit this look. 


2014
2017
dpla