Epic 2.5.1: basis for framing layer

flow-state/src/engine/Layer.js

@@ -99,6 +99,14 @@ export function setFrameUniforms(layer, renderer, target, ctx) {
         else u[name].value = v;
     }
 
+    // Framing is per shot and wins over the personality's neutral defaults —
+    // it is the operator's hand on a shot that is already set up, not a trait
+    // of the track. See look/framing.js.
+    if (layer.framing) {
+        u.u_sigFrameScale.value = layer.framing.scale;
+        u.u_sigFrameShift.value.set(layer.framing.shift[0], layer.framing.shift[1]);
+    }
+
     u.u_prev.value = prevTexture || null;
     u.u_hasPrev.value = prevTexture ? 1 : 0;
 }
@@ -136,6 +144,16 @@ export class Layer {
         return this;
     }
 
+    /**
+     * This shot's FRAMING — a per-shot scale/recentre pushed by the arc driver,
+     * applied inside sigCamera. A layer that is never framed renders at the
+     * neutral (full-frame) scale, so nothing predating framing changes.
+     */
+    setFraming(framing) {
+        this.framing = framing || null;
+        return this;
+    }
+
     /** Resolve base params + reactive modulation into the values used this frame. */
     resolveParams(features) {
         const defs = this.module.params || {};