Trail Rush

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a browser-playable Three.js endless downhill trail-dodging game titled “Trail Rush.” Use a third-person chase camera behind and slightly above a compact stylized bike rider, looking down a long brown trail that recedes toward the horizon. The world should have a pale cyan sky with matching atmospheric fog, simple low-poly green banks on both sides of the trail, and two distant faceted snow-colored mountain cones. Build the trail from repeated wide brown rectangular downhill segments, with broad light-green side banks and a darker green inner edge/shadow along the road. Enable soft shadows, a warm directional sun, cool fill/rim lighting, mild ACES-style tone mapping, and clean low-poly geometry.

The player is a small readable bike/rider silhouette near the bottom center: two black/dark circular torus wheels side-by-side across the screen, a short teal horizontal frame, dark seat and handlebar, an orange capsule-like leaning rider body, and a yellow spherical helmet/head. Place the rider on the trail and have it bob subtly while moving. The rider can steer horizontally only, clamped within the road: hold A/D or the left/right arrow keys, or use large touch-friendly ◀ and ▶ buttons at the bottom corners. Smoothly move the bike left/right at about 6.6 units per second, tilt it slightly into the steering direction, and have the chase camera follow some of the horizontal movement while looking ahead down the trail.

Make it an endless run. Distance starts at 0 m and increases continuously over time, initially about 11 meters per second with a gradual capped acceleration. Spawn obstacle waves ahead of the rider around z=-72 and move them toward the camera/rider, making the trail feel like it is rushing downhill. Use three approximate lanes at x=-3.2, 0, and 3.2. On each wave randomly choose one safe lane, then usually place obstacles in the other two lanes, with slight random horizontal offsets. Obstacles are either stylized pine trees or rocks, loaded from the Kenney nature assets if available: pine tree asset `tree_pineDefaultA.glb` and rock asset `cliff_block_rock.glb`; trees should be somewhat larger than rocks and both should cast/receive shadows. Spawn waves roughly every 1.22 seconds initially, gradually shortening only down to about 0.62 seconds. As obstacles pass beyond the player/camera, remove them.

Detect a wipeout when an obstacle is close in both horizontal and depth distance (tree collision radius about 0.82, rock about 0.68, depth threshold about 0.9). End the run immediately on collision, save the highest whole-meter distance in localStorage, and do not add lives, health, weapons, collectibles, jumping, braking, or other mechanics. While running, update the HUD continuously with whole-meter distance. On game over, stop movement, show “WIPEOUT” and the subtitle “THE TRAIL WON THIS RUN,” hide the controls hint, and show a green “RIDE AGAIN” button that resets the rider, distance, obstacles, and run state. Also allow the R key to restart after a wipeout.

Overlay a minimal fixed HUD over the canvas: upper-left bold spaced title “TRAIL RUSH”; upper-right right-aligned “DISTANCE [green value]” and “BEST [green value]”; centered near the upper fifth of the screen the instruction “STEER WITH A / D OR THE ARROW KEYS.” Use white/cyan text with subtle dark shadows. Put translucent dark blue rounded rectangular left/right touch buttons along the bottom, each about 76x58 pixels, with a soft shadow and white triangle glyph. Make the layout responsive, keep the canvas full-screen, prevent page scrolling/touch gestures, and on wider screens constrain the button row to a modest centered width while slightly reducing button opacity.