OpenGLContext Hill Runner Demo

OpenGLContext engine demo that creates an endless runner game down a valley on a hill. Demonstrates tiles3d on-demand tile creation, GPU accelerated animations, vegetation, GUI widgets and the Heads Up Display.

uv run --pre --with openglcontext-hill-runner oglc-hill-runner

Or you can pip-install it and run like so:

oglc-hill-runner                # the main screen: play, demo, settings, credits, quit
oglc-hill-runner --demo         # the autopilot plays, with no main screen
oglc-hill-runner --seed 7       # a different hill
oglc-hill-runner --no-sound --size 1920 1080
oglc-hill-runner --no-forest --no-photos   # no use of the forest demo's art or the engine's textures, no download
oglc-hill-runner --yes            # fetch the packs below without asking, where they are not here
oglc-hill-runner --record run.mp4 # the autopilot's run, recorded to a 30 second video

The game runs on three downloads, all under Creative Commons terms: its own art and sound (the runner, the music, the sounds), the forest demo's trees and ground cover, and the engine's photographic textures (CC0). The first run lists them with their sizes and terms, asks once and fetches them into the per-user content store; later runs find them there. A checkout holding the art in src/openglcontext_hill_runner/assets does not fetch its own pack.

Recording

--record PATH records the autopilot's run to an MP4 file and exits when the video is done. It implies --demo and --no-sound: the run is the autopilot's, there is no main screen, and the file has no audio track.

oglc-hill-runner --record run.mp4 --record-codec hevc --record-seconds 20
oglc-hill-runner --record run.mp4 --record-codec av1 --record-fps 30 --seed 7 --size 1920 1080

The world advances by exactly one frame's worth of time for each frame written, so the video is smooth however long the frames took to draw, and the same seed records the same course. A recording is not in real time: 120 seconds of video takes as long to record as its frames take to draw, and a line every five seconds says how far along it is and how long is left. A run that is cut off leaves a video that plays up to a second or so before the end. The video is the size of the window's framebuffer, which is larger than --size on a display with scaling. Recording needs OpenGLContext[video], which this package depends on, and a GPU video encoder: see OpenGLContext's docs/recording.rst for which GPUs and platforms have one.

Playing

The three trails are 0.5 m wide with 0.2 m between them, so a hop is one big step. The runner speeds up from 10 to 24 m/s and cannot slow down on its own. A log, a boulder, a gate board or a wall is a hit; they stand across one or two trails and are a metre high or more. Coins hang at knee height and are worth 1 coin. Jewels hang above a runner's reach and are worth 5 coins: they need a jump. The HUD shows coins, score, hits and metres run.

Hits and continues

A hit knocks the runner down just short of the obstacle. It stays there for 1.3 s, rolling to its feet, with the keys doing nothing, and then runs on from 10 m/s: the speed gained is lost. Each hit costs a continue of 100 coins. The edges of the screen turn red and flash at the hit, and the coins flash red as they count down by 100 over the 1.3 s of the roll. When the 100 are paid the red clears and the runner runs on. A runner with fewer than 100 coins cannot buy a continue: the run is over at the hit, with the edges red, and the coins it has are kept and shown on the end screen. The score is not spent. Nothing hits the runner again for the next 15 m, so a row of obstacles is one hit.

The country

The hill runs through forest, rocks, sand, meadow and dense forest, a few hundred metres of each, in an order the seed picks. The land, the ground, the trees, the ground cover and the rocks change with it. The trail wanders from side to side.

Caves

Every two or three kilometres, after a stretch of rock country, the trail runs into a cave. The valley is filled up to the height of the hills beside it over 22 m, so the trail runs into the foot of a hillside and the cave is a hole bored through it: the ground is tessellated out to the rim of the opening, and the tunnel runs from there to a second opening in the far side of the hill. The tunnel is 250 to 320 m long, an arch swept along a spline through the trail and cut into rock: flat facets, steps and pits (OpenGLContext.scenegraph.rockwork). It leads out into more rock country or into forest, the seed's choice.

• The ceiling is high in places (4.4 to 7.5 m over the floor) and low in others (2.4 to 3.0 m), changing over 16 m. Running or sliding under a low ceiling is safe; a jump under one is a hit, and so is a jump at the edge of one, since the head arrives at the top of the jump. The camera sinks under a low ceiling and rises again once it is clear; where it has sunk it stands to the right of the runner and looks across to the left, so the runner does not hide what is ahead.
• A crevice runs right across the floor, 1.8 m wide and 2.6 m deep. It has to be jumped, and a runner who is on the ground over it is a hit. Crevices stand only where no low ceiling is within 14 m, so the jump a crevice asks for is always safe; so is every jump the course asks for in a cave, and the jewels that hang out of reach of a standing runner.
• The logs, boughs and walls of the open hill are in caves too. A fallen log under a low ceiling is a bough to slide under instead.
• A torch on the wall every 18 m, on alternate sides, is all the light there is. The sun, the sky's light and the haze go out over the first 28 m inside the mouth. The torches' lights are the nearest of the scene's lights, which is what the engine binds when there are more than it has room for.
• No fork runs near a cave, and no trees or ground cover grow over one. The stone of an obstacle is paler than the rock about it and glows a little, so it shows in shade.

Forks

Every kilometre or so two more paths appear beside the trail, on the left or the right. They draw away and run through another country, then come back and join. Hop onto them in the first few seconds, while they are within a hop of the trail; after that they are on a trail of their own. A path that joins the trail carries its runner onto the nearest path of it.

What it uses from the engine

How it is put together

The rules have no GL and are tested without a window.

Tests

pip install -e ".[dev]"
pytest

The render smoke test skips where there is no display.

Assets

Audio and the character are CC0. The music is Medieval: Market Day by RandomMind. The forest demo's tree models are CC-BY 4.0 and credited on launch. ASSET-LICENSES lists each file. The character's Slide clip is made by grass-clumps/slide.py in the OpenGL-dev workspace.

The runner, the music and the sounds (2.7 MB) are a content pack, openglcontext-hill-runner/assets, attached to a GitHub release and not carried in the wheel. The first run lists the pack's size and terms and asks before it fetches it; a checkout runs from its own copy and asks nothing. release-assets.py builds the pack and writes the registry the game ships (packs.json); tools/publish-content.py in the workspace attaches it to its release.