{"id":28902570,"url":"https://github.com/bbbbbr/rolly_scrolly_gameboyshowdown_2025","last_synced_at":"2025-08-22T00:07:49.137Z","repository":{"id":294579684,"uuid":"987401804","full_name":"bbbbbr/rolly_scrolly_gameboyshowdown_2025","owner":"bbbbbr","description":"Hastily made little GB Demo for Game Boy Showdown 2025","archived":false,"fork":false,"pushed_at":"2025-05-21T04:10:24.000Z","size":329,"stargazers_count":0,"open_issues_count":0,"forks_count":0,"subscribers_count":1,"default_branch":"main","last_synced_at":"2025-05-21T05:22:59.474Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":null,"language":"C","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"unlicense","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/bbbbbr.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null}},"created_at":"2025-05-21T02:58:42.000Z","updated_at":"2025-05-21T04:10:27.000Z","dependencies_parsed_at":"2025-05-21T05:23:02.505Z","dependency_job_id":"ce87cb88-eb9c-4260-94f8-2789150f13ed","html_url":"https://github.com/bbbbbr/rolly_scrolly_gameboyshowdown_2025","commit_stats":null,"previous_names":["bbbbbr/rolly_scrolly_gameboyshowdown_2025"],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/bbbbbr/rolly_scrolly_gameboyshowdown_2025","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/bbbbbr%2Frolly_scrolly_gameboyshowdown_2025","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/bbbbbr%2Frolly_scrolly_gameboyshowdown_2025/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/bbbbbr%2Frolly_scrolly_gameboyshowdown_2025/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/bbbbbr%2Frolly_scrolly_gameboyshowdown_2025/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/bbbbbr","download_url":"https://codeload.github.com/bbbbbr/rolly_scrolly_gameboyshowdown_2025/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/bbbbbr%2Frolly_scrolly_gameboyshowdown_2025/sbom","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":261110615,"owners_count":23111067,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":[],"created_at":"2025-06-21T11:09:39.955Z","updated_at":"2025-08-22T00:07:49.105Z","avatar_url":"https://github.com/bbbbbr.png","language":"C","funding_links":[],"categories":[],"sub_categories":[],"readme":"## Rolly Scrolly Demo\n\nHastily made little GB (And MegaDuck) Demo for Game Boy Showdown 2025 with a Cylinder like effect and some wraparound sprite text.\n\nROM downloadable on itch.io:\nhttps://bbbbbr.itch.io/rolly-scrolly-demo\n\n### Effect\n![Diagram of effect](info/rolly_scrolly_diagram.png)\n\nFor the Cylinder:\n- Per scanline Y scroll adjustments from a pre-computed table (made in a spreadsheet) that create the cylinder distortion\n- There is a matching set of per scanline GB palette adjustments which darken the colors toward the top and bottom of the cylinder\n\nFor the bounce:\n- There's a per-frame sine wave table that adjusts where the cylinder is located (by setting an initial Y scroll offset which the cylinder code factors in)\n\nFor the Text:\n- The entire cylinder only uses Background (BG) colors 1-3, and the area outside of it is all scrolled to a single line which only uses BG color 0. This is important for the next part\n- For hiding the text that goes \"behind\" the cylinder the sprites on the left 1/4 and right 1/4 of the screen have their BG priority set so that they only show up over BG color 0 (above and below cylinder area) and are hidden by anything with BG color 1-3 (inside cylinder area)\n- Then there is a second sine wave table which is used for the text Y position, this is just indexed based on the sprite X position\n\n### Building\nBuilt with GBDK-2020 4.4.0\n\n\n\n\n\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fbbbbbr%2Frolly_scrolly_gameboyshowdown_2025","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fbbbbbr%2Frolly_scrolly_gameboyshowdown_2025","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fbbbbbr%2Frolly_scrolly_gameboyshowdown_2025/lists"}