Flip Flap

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 mobile-friendly 2D Flappy Bird-style side-scrolling game titled “Flip Flap,” rendered with a Three.js orthographic camera so the playfield stays flat and cartoon-like while filling the viewport responsively. The camera should show a bright cyan-blue sky, soft white semi-transparent clustered clouds drifting slowly, rounded green hills along the horizon, and a horizontal dirt-colored ground band at the bottom topped by a thin vivid grass strip. Keep the visual style simple, colorful, chunky, and clean with flat materials and no textures.

The player is a small animated yellow bird fixed near the left side of the screen (about x=-4.5 in world coordinates). Build it from simple shapes: a round yellow body with a pale cream belly, orange oval wing, orange triangular beak pointing right, and a white eye with a dark pupil. Animate the wing continuously and give it a brief stronger flap animation on input. Tilt the bird according to its vertical velocity: nose-up while rising and nose-down while falling.

Core gameplay: the bird is affected by constant downward gravity and automatically flies to the right relative to a stream of obstacles. Tapping/clicking anywhere, pressing Space, ArrowUp, or W gives a flap impulse upward (vertical velocity about +5.2); there is no horizontal player control. The world scrolls by moving pipe sets leftward at an initial speed around 5 world units/second, gradually increasing but capped around 7.2. The bird must pass through the vertical gaps between pairs of chunky green pipes. Each pipe set consists of a top and bottom green rectangular pipe, each with a brighter, wider lip at the opening and a dark green shaded strip along its left side. Pipe width is about 1.25 world units, gaps about 3.05 units high, and each gap is randomly positioned vertically while leaving safe margins from the ceiling and ground. Start with three pipe sets ahead of the bird, then continuously spawn new sets roughly 4.35 units after the rightmost one; remove sets once they leave the left side. Pipe spacing should create a steady arcade challenge.

Collision rules: touching a pipe, the ground, or the upper ceiling immediately ends the run. Use the bird’s circular body for forgiving collision checks against the pipe opening. The bird also dies if it falls below the ground or rises above the ceiling. Passing completely beyond the right edge of a pipe gap awards exactly 1 point, shown in a large centered white number at the top with a subtle dark shadow. Store and display a best score across runs if supported.

Gravity-reversal twist: pipe sets numbered 4, 8, 12, etc. should contain a collectible glowing gravity ring centered in their gap. The ring is a purple outer ring with a smaller yellow glowing core and several white/yellow sparkles around it; it should slowly rotate and pulse. When the bird flies through the ring (within roughly 0.95 world units), hide/deactivate it and reverse the gravity behavior for 5.5 seconds. During reversal, gravity pulls upward instead of downward, and flap input pushes the bird downward with an impulse of about -5.2 rather than upward. The sky should briefly flash purple when the ring activates and remain subtly lavender-tinted during the active reversal. Show a purple rounded HUD panel at the upper-right only while reversal is active, with a glowing yellow circular icon, the label “GRAVITY,” and a countdown timer in seconds with one decimal place. Once the timer reaches zero, restore normal gravity and upward flaps.

Input should work immediately from the title/ready screen and after game over: the first tap/click/keyboard flap starts or restarts the game and gives the initial flap impulse. On the ready screen, show a centered translucent dark overlay and a large rounded white card with a yellow/orange outlined “Flip Flap” title, the instructions “Clear pipe gaps for points.” and “Fly through glowing rings to reverse gravity — then flaps push down.”, plus a green pill-shaped “Tap to start” button. During active play, hide the card and show a bottom hint reading “Tap / Click / Space to flap.” On game over, show the overlay card again with the title “Game Over,” the best score, the final score, and the message “Tap, click, or press Space to try again.” with a green “Restart now” button. Make the UI touch-safe, prevent page scrolling/selection, and use responsive sizing for portrait and landscape screens.