ludic/changes/leaves-light-and-the-bole.md

bump: minor type: feat Three things a crown and a hand light were getting wrong.

An aspen's trunk quaked with its leaves. layer_flutter's mask was the vertex's HEIGHT alone — anything more than 1.2 m up trembled — so on a ten metre aspen the whole bole moved, and a tree that is supposed to shiver read as a column of cloth. What separates a leaf from a bole is not height, it is distance from the model's own centre line: the leaves are out at the edge of the crown and the trunk is on the axis. The mask is radial now, and small plants keep the old one, because a flower is all leaf.

Foliage in the camera's face. A third-person camera walks into a crown and the branch between it and the body is an opaque wall a metre from the lens; in first person it is the whole screen. #define NEAR_FADE dithers tree foliage out inside arm's length of the camera — in the depth PREPASS, so the lit pass never sees those pixels either and the equal-depth optimisation is untouched. gl_Position.w is the view depth for a perspective projection, so it costs one varying and no uniform. Blades, cards and flowers are left alone on purpose: they live at the player's feet, they are always that close, and fading them opens a hole in the meadow. Nor is the BOLE ever faded: a trunk and its needle cards are one mesh drawn by one program, so the first cut dissolved the trunk into a dither pattern as you walked up to it - a solid tree you can see through reads as a fault, where a branch getting out of your way reads as the camera being polite. The mask is the same signal the quake uses. The shadow pass keeps every leaf, or a tree would stop shading the ground it stands on as you walked up to it.

A hand light had the reach of a candle, whatever it was meant to be. handLight's falloff was an inverse square windowed off between 26 and 6 metres, with both numbers hard-coded: two per cent of its own near field by ten metres out, so carrying a torch at night lit your boots and nothing else. daylight_hand takes a reach in metres now and the falloff is a gentle power out to it — about nine tenths at a metre, half at half the reach, a tenth at nine tenths of it, nothing past it. A pool of light with a gradient in it rather than a hotspot with a cliff.

And the wheel on macOS did nothing, or everything. scrollingDeltaY is a double, and the Cocoa event pump truncated it to an int PER EVENT before accumulating: a trackpad or a Magic Mouse sends a stream of fractions of a line, every one of which truncated to zero, so the wheel was dead; a notched mouse sends three to ten lines at once, so it jumped. The fraction is accumulated now, a precise delta is scaled from points to notches, and the remainder carries to the next frame - one gesture, one step, on both kinds of mouse.