Callback: Cargo sub-type display for industries
From GRFSpecs
Jump to navigationJump to searchCargo sub-type display for industries (37)
This callback allows you to display some text after the cargo name in the industry fund window and in industry windows.
GRFv7 For GRF version 7 and below the valid return values are:
| 00..FE | Display D0xx (D000..D0FE) text. |
| FF | Display no text. |
| 100..1FE | Display D0xx (D100..D1FE) text. |
| 200..2FE | Display D0xx (D200..D2FE) text. |
| 300..3FE | Display D0xx (D300..D3FE) text. |
GRFv8 For GRF version 8 and above the valid return values are:
| 00..3FF | Display D0xx (D000..D3FF) text. |
| 400 | Display no text. |
During the callback, the lowest byte of var. 18 can have the following values:
| Number | Meaning |
|---|---|
| 00 | Return subtext for first accepted cargo type |
| 01 | Return subtext for second accepted cargo type |
| 02 | Return subtext for third accepted cargo type |
| 03 | Return subtext for first produced cargo type |
| 04 | Return subtext for second produced cargo type |
Bits 8..15 of var. 18 can have the following values:
| Number | Meaning |
|---|---|
| 00 | The text is to be displayed in the industry fund window. The industry isn't built yet, so you can't access the industry variables |
| 01 | The text is to be displayed in the window of the industry. You can use the industry variables here. |
| 02 | The text is to be displayed in the industry directory window. You can use the industry variables here. |
| other values | Reserved for future use |
Other bits of var. 18 are reserved for future use.
1.0 
Since OpenTTD r17802, the contents of registers 100h..105h are copied onto the text reference stack.
