Procedural animated texture generation/Compasses
This feature is exclusive to Java Edition and Legacy Console Edition.
Compasses simply draw two lines over the item sprite to form the needle.
Much like clocks, the code responsible for moving the needle is also present with the "setup" code, however it is omitted here as it is not pertinent to the actual drawing of the sprite. Also like clocks, an oversight in how the compass sprite is set to be loaded prevents texture packs from overriding the compass's base sprite.
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The base sprite for the compass
def setup_compass_sprite (item: Image, angle: float, output: Image):
NX = 8.5
NY = 7.5
SCALE_X = 0.3
SCALE_Y = SCALE_X * 0.5
# copy the item's texture into the output
for i, pix in enumerate(item):
output.set_pixeli(i, pix)
rx = sin(angle)
ry = cos(angle)
# draw the smaller horizontal spurs of the needle
# 1 is added to the endpoint, as `range` here is
# end-exclusive. The original loops did `i <= 4`
for i in range(-4, 4 + 1):
x = int(NX + ry * i * SCALE_X)
y = int(NY - rx * i * SCALE_Y)
output.set_pixel(x, y, '#646464')
# draw the main part needle
for i in range(-8, 16 + 1):
x = int(NX + rx * i * SCALE_X)
y = int(NY + ry * i * SCALE_Y)
if i >= 0:
# Main red pointer
output.set_pixel(x, y, '#FF1414')
else:
# Grey back half
output.set_pixel(x, y, '#646464')
The generated compass sprite has 102 possible unique frames, while the pre-rendered compass has significantly less, at only 32 frames.
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Procedurally generated -
Prerendered frames -
Visualization of all of the points that are plotted in drawing the needle