# Voxel Height Grid Builder

> Build an editable voxel model from rows of integer heights. Turn a rectangular grid of integer heights into a colored voxel model. Download a transparent isometric SVG, an OBJ/MTL mesh, a single-model VOX file, and an editable project for Renderloom Voxel Desk.

Part of usefulweb.site (https://usefulweb.site/). Results are deterministic calculations from the inputs and the listed assumptions; the API returns exactly what the web page shows.

## Use it
- Human interface: https://renderloomvoxelheightgrid.usefulweb.site/ (interactive tool at https://renderloomvoxelheightgrid.usefulweb.site/tool)
- JSON API: POST https://renderloomvoxelheightgrid.usefulweb.site/api/v1/calculate with a JSON object of inputs (schema: https://renderloomvoxelheightgrid.usefulweb.site/api/v1/tool)
- OpenAPI: https://renderloomvoxelheightgrid.usefulweb.site/openapi.json
- MCP (Streamable HTTP): https://renderloomvoxelheightgrid.usefulweb.site/mcp - tool `renderloom_voxel_height_grid`

## Inputs
- grid (textarea): Height grid (0–64; one row per line)
- base (text): Base color (#rrggbb)
- top (text): Top color (#rrggbb)

## Method
- Each cell specifies the number of voxels in a solid vertical column. Zero leaves a column empty. Values must be integers from 0 to 64; rows must have equal widths.
- The highest voxel in each nonempty column uses the top color and all lower voxels use the base color.
- A voxel occupies one integer grid cell; X and Y span each row and Z is the vertical axis. The preview is a transparent orthographic isometric illustration with fixed face shading.
- The model supports dimensions of 1–64 cells per axis, up to 32,768 occupied cells and up to 64 opaque palette colors.
- The VOX export is a single-model VOX 150 file with opaque palette colors. The OBJ mesh contains outward-facing quads only where a voxel has no occupied neighbor. It uses palette-based MTL diffuse colors; it does not include textures, animation or physically based material properties.

## Limits
- This creates solid vertical columns from the grid. The preview uses fixed illustration shading; it is not a physically based render.