Why 0.999… Equals 1
A pupil's guess, 0.999… < 1 ?, sits on the board. The teacher multiplies 1/3 = 0.333… by 3 in orange chalk to get 3/3 = 0.999…, wipes the guess in one pass and writes 0.999… = 1 in its place, underlined.
Chalkboard · 16:9 · 10.0s
Chalkboard
A real classroom blackboard in deep ink green, with its wooden frame, chalk tray and wall: chalk writes by itself stroke by stroke in true stroke order, with pressed starts, sharp sweeps and footed strokes, and English in a single-line handwriting, with no hand or chalk in sight. White chalk carries the structure, one orange chalk tracks the one part the lesson is about, and a pupil's pale yellow guess is wiped away in one pass and rewritten correctly in the same place as the wet streak dries. The camera faces the board and pushes in from a wide shot of the room. Made for short lessons on one idea: where a word or character comes from, a misconception set right, a worked problem.
Use this style- Good for
- Math explainer
- Footage
- Tags
- Format
- 16:9 1920×108030fps
What to provide
Tell us the one point of the lesson, the few keywords to write on the board (one line of Chinese and/or one of English), the part to track in the accent chalk, and whether a wrong idea should be written and then wiped and corrected. Give sources for dates, numbers and word origins. Everything is drawn in code, so no images are needed; the voice-over and subtitles explain, the board holds keywords only.
What you can change
- accent
- 整片唯一的强调色粉笔，默认橙色，只用于课上追踪的那一个部件；可换成另一种单色粉笔（黄、蓝、红、绿、紫、青），不能加第二种强调色
- hands
- 白色是老师的字和所有结构；淡黄色的孩子笔迹用于学生的问题或错误答案（可擦掉后在原处重写）
Limitations
- 只支持 16:9 横版、30 fps
- 板上只写关键词：一行中文、下一行英文；讲解靠平台口播与字幕
- 汉字按笔画数据书写：包里自带一批手写数据，其余字由字形自动求笔画，求不全的字（漏部件、断笔）会被拒绝，需在段里补写笔画数据；大字与追踪部件建议都给手写数据
- 英文用单线手写字体，只有拉丁字母、数字和常用符号；每片最多一次擦除
- 日期、数字与字源只取已确认内容，不编造
- 全部由代码绘制，不使用照片或视频素材
- 不自带配乐与音效（包括粉笔声）