Protect rendering performance
For a game designer, this catalog design prototype should make every player action and player-visible outcome easy to evaluate. Write how to define item identity, value, Koin price, preview, and ownership before checkout. Choose the offer moment, explain the game benefit, and protect the complete free path. Compare the experience before and after ownership. Open and close the interface during GPU-heavy scenes, then monitor input, frame pacing, and canvas recovery. A commerce overlay should not leave the game loop paused or controls captured unexpectedly.
Coordinate DOM and canvas state
Make the selected item and outcome visible in both interface and gameplay context. Handle focus loss, pointer lock, fullscreen transitions, and a resized canvas around confirmation and return.
Exercise context recovery
Simulate refresh, background suspension, and a lost rendering context. The player-facing purchase result should reconcile separately from graphics recovery and must never duplicate an item.
Judge the offer in the core loop
Run the game without opening the purchase choice, then run it with the item. Compare pacing, motivation, difficulty, and recovery so the offer supports play instead of repairing frustration that was added deliberately.
Make the player promise concrete
Describe what changes on screen, how long it lasts, where it appears, and what remains available without it. Replace value labels such as better or premium with rules a player can observe.
Review the moment of choice
Check what the player was doing immediately before the offer and where cancel returns them. The item should arrive after enough context to understand it, but never during a time-critical or emotionally pressured action.
Compare items consistently
Use the same fields for every offer: preview, benefit, ownership or duration, full price in Koin, and owned state. Consistent cards make differences easier to understand. Test that behavior using WebGL games. WebGL rendering and commerce state need separate failure testing.
Keep the first catalog small
Start with one to three clearly different items. A large grid makes it harder to find unclear value, duplicated promises, and missing delivery states. Test that behavior using WebGL games. WebGL rendering and commerce state need separate failure testing.
Design owned and unavailable states
A catalog also needs sold, owned, equipped, and unavailable presentations. Do not leave a purchased item looking buyable after reload. Test that behavior using WebGL games. WebGL rendering and commerce state need separate failure testing.