import scene3d
scene = scene3d.Scene()
scene.set_ground(length=10, width=10)
sphere = scene3d.Shapes.Sphere(diameter=1, segments=16)
sphere.set_position(0, 0.5, 0)
scene.add(sphere)
scene.run()Colors
Every shape in a 3D scene starts out grey — and it’s up to you to bring it to life. In Python, colors are written as hex codes: a # sign followed by six digits that blend red, green, and blue light together.
In this lesson you’ll learn how hex codes work and use them to paint the sky, the ground, and every shape in your scene.
A Colorless World
Run the cell below. Notice anything missing? The sphere appears, but it’s a flat grey — and the sky is almost black. That’s what a scene looks like with no colors applied.
How Hex Colors Work
Every color is made from three ingredients: Red, Green, and Blue. A hex color code packs all three into one short string:
#e94560The # marks the start. After that come three pairs of digits:
| Pair | Controls | 00 means… |
ff means… |
|---|---|---|---|
e9 |
Red | no red | full red |
45 |
Green | no green | full green |
60 |
Blue | no blue | full blue |
The digits go from 00 (zero) to ff (which equals 255 in regular numbers — the maximum).
Here are some colors made from pure combinations:
| Color | Hex code | Why? |
|---|---|---|
| Red | #ff0000 |
Full red, no green, no blue |
| Green | #00ff00 |
No red, full green, no blue |
| Blue | #0000ff |
No red, no green, full blue |
| Yellow | #ffff00 |
Full red + full green mixed |
| Cyan | #00ffff |
Full green + full blue mixed |
| White | #ffffff |
All three at maximum |
| Black | #000000 |
All three at zero |
Coloring the Sky and a Shape
Two function calls change the scene completely: - scene.set_sky('#color') — paints the background sky - sphere.set_color('#color') — paints the sphere
Run the cell below to see the difference from the grey world above.
import scene3d
scene = scene3d.Scene()
scene.set_sky('#87ceeb')
scene.set_ground(length=10, width=10)
sphere = scene3d.Shapes.Sphere(diameter=1, segments=16)
sphere.set_color('#e94560')
sphere.set_position(0, 0.5, 0)
scene.add(sphere){ “question_type”: “multiple_choice”, “question”: “What color does the hex code #ff0000 produce?”, “options”: [ { “key”: “a”, “text”: “Blue” }, { “key”: “b”, “text”: “Green” }, { “key”: “c”, “text”: “Red” }, { “key”: “d”, “text”: “White” } ], “answer”: “c”, “submitted_answer”: “” }
{ “question_type”: “true_false”, “question”: “The hex code #000000 produces white.”, “answer”: “False”, “submitted_answer”: “” }
Any Shape Can Be Colored
set_color works on every 3D shape — spheres, boxes, and cylinders all use the same function. The scene below places three different shapes side by side, each with its own color.
import scene3d
scene = scene3d.Scene()
scene.set_sky('#1a1a2e')
scene.set_ground(length=12, width=12)
sphere = scene3d.Shapes.Sphere(diameter=1, segments=16)
sphere.set_color('#e94560')
sphere.set_position(-3, 0.5, 0)
scene.add(sphere)
box = scene3d.Shapes.Box(width=1, height=1, depth=1)
box.set_color('#4488ff')
box.set_position(0, 0.5, 0)
scene.add(box)
cylinder = scene3d.Shapes.Cylinder(diameter=1, height=1.5, tessellation=16)
cylinder.set_color('#44cc88')
cylinder.set_position(3, 0.75, 0)
scene.add(cylinder){ “question_type”: “multiple_choice”, “question”: “Which hex code produces yellow?”, “options”: [ { “key”: “a”, “text”: “#ff00ff” }, { “key”: “b”, “text”: “#00ffff” }, { “key”: “c”, “text”: “#ffff00” }, { “key”: “d”, “text”: “#ff0000” } ], “answer”: “c”, “submitted_answer”: “” }
Design Your Own Palette
Use the dropdowns below to pick colors for the sky, the sphere, and the box. Change the values and run the cell to see your choices in action.
import scene3d
SKY_COLOR = '#1a1a2e' #@param ['#1a1a2e', '#87ceeb', '#ff6b35', '#0f3460', '#2d5a27']
SPHERE_COLOR = '#e94560' #@param ['#e94560', '#4488ff', '#44cc88', '#f5a623', '#aa44ff']
BOX_COLOR = '#f5a623' #@param ['#e94560', '#4488ff', '#44cc88', '#f5a623', '#aa44ff']
scene = scene3d.Scene()
scene.set_sky(SKY_COLOR)
scene.set_ground(length=10, width=10)
sphere = scene3d.Shapes.Sphere(diameter=1, segments=16)
sphere.set_color(SPHERE_COLOR)
sphere.set_position(-2, 0.5, 0)
scene.add(sphere)
box = scene3d.Shapes.Box(width=1, height=1, depth=1)
box.set_color(BOX_COLOR)
box.set_position(2, 0.5, 0)
scene.add(box)Coloring the Ground
The sky gets its color from set_sky. But what about the ground? The built-in ground plane doesn’t have a color setting — so instead, we can place a wide, flat Box right at ground level and color that.
This turns out to be a useful trick: a Box with a small height and large width and depth becomes a colored floor for the whole scene.
import scene3d
scene = scene3d.Scene()
scene.set_sky('#0f3460')
floor = scene3d.Shapes.Box(width=12, height=0.1, depth=12)
floor.set_color('#2d5a27')
scene.add(floor)
sphere = scene3d.Shapes.Sphere(diameter=1, segments=16)
sphere.set_color('#e94560')
sphere.set_position(-2, 0.55, 0)
scene.add(sphere)
cylinder = scene3d.Shapes.Cylinder(diameter=1, height=1.5, tessellation=16)
cylinder.set_color('#f5a623')
cylinder.set_position(2, 0.8, 0)
scene.add(cylinder){ “question_type”: “true_false”, “question”: “In a hex color code, the value ff equals 255 in regular decimal numbers.”, “answer”: “True”, “submitted_answer”: “” }
{ “question_type”: “multiple_choice”, “question”: “What color does #00ffff produce?”, “options”: [ { “key”: “a”, “text”: “Purple” }, { “key”: “b”, “text”: “Yellow” }, { “key”: “c”, “text”: “Orange” }, { “key”: “d”, “text”: “Cyan (blue-green)” } ], “answer”: “d”, “submitted_answer”: “” }
{ “question_type”: “freeform”, “question”: “What is the name of the function used to set the sky color on a scene?”, “answer”: “set_sky”, “submitted_answer”: “” }
Look at the color mixing table in this lesson (red + green = yellow, green + blue = cyan, etc.).
Can you predict what red + blue mixed together would make? Write your prediction, then try it — set a sphere’s color to #ff00ff and see if you were right!