Mesh Draw Range

App: apps/mesh_draw_range/

Uses setDrawRange and clearDrawRange to reveal a grid of triangles over time: a sine wave drives how many vertices are “visible,” so triangles appear progressively (then hide and repeat).

Run from root

% ./plume3d mesh_draw_range

or

Run from app directory

% ./../plume3d .

What it does

• Builds a 5×5 grid of small triangles (each cell = 3 vertices), draw mode "triangles".
• In update: ratio = (Math.sin(_time) + 1) / 2, then visibleCount = floor(ratio * totalVertices) aligned to a multiple of 3.
• If visibleCount > 0: _mesh.setDrawRange(0, visibleCount); else _mesh.clearDrawRange().

APIs

• Graphics — loadShader, newMesh, drawMesh.
• Mesh — getVertexCount, setDrawRange, clearDrawRange.
• Math — sin, floor.