@thi.ng/rasterize/draw.js

Headless 2D shape drawing, filling & rasterization for arbitrary targets/purposes (no canvas required)

import { isFunction } from "@thi.ng/checks/is-function";
import { isPrimitive } from "@thi.ng/checks/is-primitive";
const __draw2D = (pts, grid, val) => isFunction(val) ? __drawShader2D(pts, grid, val) : __drawSolid2D(pts, grid, val);
const __drawSolid2D = (pts, grid, val) => {
  if (!pts) return grid;
  if (isPrimitive(val)) {
    const {
      data,
      offset,
      stride: [sx, sy]
    } = grid;
    for (const p of pts) {
      data[offset + p[0] * sx + p[1] * sy] = val;
    }
  } else {
    for (const p of pts) {
      grid.setAtUnsafe(p[0], p[1], val);
    }
  }
  return grid;
};
const __drawShader2D = (pts, grid, shader) => {
  if (!pts) return grid;
  if (isPrimitive(grid.getAtUnsafe(0, 0))) {
    const {
      data,
      offset,
      stride: [sx, sy]
    } = grid;
    for (const { 0: x, 1: y } of pts) {
      data[offset + x * sx + y * sy] = shader(grid, x, y);
    }
  } else {
    for (const { 0: x, 1: y } of pts) {
      grid.setAtUnsafe(x, y, shader(grid, x, y));
    }
  }
  return grid;
};
export {
  __draw2D,
  __drawShader2D,
  __drawSolid2D
};