Data File: Art.mul
Index File: ArtIdx.mul
There are three types of art images; land, static, and UO alpha
Land images are of flat terrain.
Static images are of items (walls, equipment, food, etc)
UO alpha images are a sort of animated characters, they used these instead of Anim.mul in the UO alpha.
Static and UO alpha images share the same format, while Land images use another.
Land:
Dim imageColors(1024) As Short
Land images are fixed size at 44x44.
They also have fixed transparent locations, and the format is optimized for this.
To read the first 22 lines, you first initialize X to 22, Y to 0, and LineWidth to 2
Then repeat the following 22 times:
Decrease X by 1
Read and Draw (LineWidth) number of pixels
Increase Y by 1
Increase LineWidth by 2
For the last 22 lines, do the following:
Read and Draw (LineWidth) number of pixels
Increase X by 1
Increase Y by 1
Decrease LineWidth by 2
The resulting image is the diamond shaped tile.
Statics:
Dim header As Integer ' Unknown
Dim width As Short
Dim height As Short
Dim lookupTable(height) As Short
Offset-Run data...The lookup table is offset from the data start, and treats the data by 16-bits.
To get the proper byte offset, you need to add 4 + height, then multiply by two.
The static images are compressed with an offset-run encoding.
Offset-Run data:
Dim xOffset As Short
Dim xRun As Short
Dim runColors(xRun) As Short
If xOffset is 0 and xRun is 0, the line has been completed. If not, continue reading the chunks.
Processing the Offset-Run data is simple:
Increase X by xOffset
Foreach xRun
Read and Draw the next pixel
Increase X by 1
End Foreach
When the line is completed, simply reset X to 0, increase Y, and seek to the next lookup in the lookupTable array and continue.
See Also:
- UO Color Format
- Index Files
