Image to Map Converter (v1.1.1)for Heroes of Might and Magic III: Horn of the Abyss

Convert an image into terrain in a downloadable, editable, playable .h3m file for Heroes III: HotA. Use the settings in the sidebar to define the allowed terrain types, adjust how the image is processed, and more.

Note: Exported maps often have buggy terrain sprites. To fix this, simply open the file in the map editor and paint a small patch of terrain anywhere; the editor will automatically correct the sprites across the map.

Input

Input type

Image Image + existing map Geographic location (beta)

Source image(s)

Two-level map

Terrain

Map size

Color clusters

Allowed terrain

Natural terrain

Unchecked = no coastal sprites or terrain variety.

Advanced terrain options

Optional matching tweaks. Positive match bias makes a terrain more likely to be chosen. Hue, saturation, and lightness shift the terrain color used for matching without changing the final terrain palette.

Image processing

Brightness (10)

Contrast (25)

Saturation (50)

Clean speckles

Preserve aspect ratio with crop-to-fill

Unchecked = stretch to map size.

Preview

Source

Processed

Map output

Load an image, choose terrain, then click Generate map.

Changelog:

v1.1.2
[!] Fixed Image + existing map so water and rock are exported from the finalized snapped overlay instead of restoring the original special tiles byte-for-byte.
[!] Reapplied rock/water in mode 2 as a separate final pass so invalid 1x1 special terrain does not survive export.

v1.1.1
[!] Patched bug that caused water and rock to corrupt .h3m outputs.

v1.1.0
[+] Added "Image + existing map" input type, which allows you to use images to repaint terrain on any map file without affecting water or impassable subterranean area.
[+] Improved terrain sprite outputs for "Natural terrain".

v1.0.0
[+] Released tool.