Immediate-mode 2D canvas redraws the whole frame each tick from explicit vector calls while retaining program state between frames

Immediate-mode drawing (P5LIVE’s paradigm) is the exact opposite of Hydra/GLSL/Punctual, where each frame is a stateless per-pixel texture evaluation. In immediate mode, the entire frame is redrawn from scratch each tick using explicit drawing calls (shapes, paths, text), but the program retains state between frames — variables, object positions, accumulated counts. This retained state is what enables physics simulations, particle systems with memory, and typography. It is the visual counterpart of the audio paradigm concepts (strongly-timed-sequencing / pattern-sequencing) in that the artist writes an explicit procedural sequence, not a declarative field.

Examples

A P5LIVE sketch’s draw() loop clears the background and redraws all elements each frame, but a Ball object’s position and velocity persist from tick to tick.

Assessment

Explain the key difference between stateless per-pixel shader evaluation and immediate-mode retained-state drawing. Name two visual concepts enabled by retained state that are not possible in a stateless fragment shader.