Procedural animated texture generation/Compasses
Minecraft Wiki article. Categories: Removed_features, Textures
This article is reproduced from Procedural animated texture generation/Compasses on the Minecraft Wiki. Mirrored from revision 3599025. It is licensed CC BY-NC-SA 3.0 by the Minecraft Wiki contributors — not under the Codex’s CC BY-SA 4.0, and it may not be used commercially. Edits belong upstream, not here.
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 104 possible unique frames, while the pre-rendered compass has significantly less - 32 frames are defined, but as some of these are identical, the actual effective number of unique frames is 28 and was further reduced to 27 after the Texture Update.
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Procedurally generated
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Pre-rendered frames
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Visualization of all of the points that are plotted in drawing the needle
Sources
- Procedural animated texture generation/Compasses — Minecraft Wiki, CC BY-NC-SA 3.0, revision 3599025.