NML:Alternative sprites

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Vehicles, Stations, Canals, Bridges, Towns, Houses, Industries (Tiles), Cargos, Airports+Tiles, Objects, Railtypes, Roadtypes, Tramtypes, Terrain

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Block Syntax

GRF

• GRF parameters

Item

• Property
• Graphics
• Livery override

Realsprites

Recolour sprites

Template

Spriteset

Spritegroup

Spritelayout

Tilelayout

Switch

Produce

Random switch

Cargotable

Railtypetable / Roadtypetable / Tramtypetable

If/else

While

Error

Disable items

Deactivate other NewGRFs

Testing for other NewGRFs

Overriding vehicles in other NewGRFs

Sprite replacement

• Replace TTD sprites
• Replace new sprites
• Add font glyphs

Alternative (32bpp) sprites

Town names

• Town names parts

Snow line

Parameter assignment

Setting base costs

Sorting vehicles in the purchase list

alternative_sprites

A alternative_sprites block allows you to specify alternative sprites (zoom levels and / or 32bpp) that are drop-in replacements for some real sprites in your grf. The syntax is as follows:

alternative_sprites(block_name, zoom_level, type[, filename[, mask_filename]]) {
	list of realsprites
}

block_name

block_name is the name of the replace / base_graphics, replace_new, font_glyph or spriteset-block for which you want to provide alternative sprites. zoom_level can be

zoom_level

name	zoom level	Grid size	Groundsprite with zig-zag border	Groundsprite with smooth border	offset_x, offset_y	Description
ZOOM_LEVEL_OUT_8X	8x out	8 x 4	8 x 3	8 x 3	-3, 0	zoomed-out
ZOOM_LEVEL_OUT_4X	4x out	16 x 8	16 x 7	16 x 7	-7, 0
ZOOM_LEVEL_OUT_2X	2x out	32 x 16	32 x 15	32 x 15	-15, 0
ZOOM_LEVEL_NORMAL	(normal)	64 x 32	64 x 31	64 x 31	-31, 0	The standard
ZOOM_LEVEL_IN_2X	2x in	128 x 64	128 x 62	128 x 63	-62, -1	zoomed-in
ZOOM_LEVEL_IN_4X	4x in	256 x 128	256 x 124	256 x 127	-124, -2
	(X)x in	(X*32) x (X*16)	(X*32) x floor(X*15)	(X*32) x (X*16-1)	ceil(X*-31), ceil(X*-1/2)	Generalisation

Hint: If you have a normal-zoom sprite with (offset_x, yel), the 2x zoom-in sprite will have (2*offset_x, 2*offset_y-1), and the 4x zoom-in sprite will have (4*offset_x, 4*offset_y-2).

These conversions are implied by how OpenTTD draws foundations, in particular half-tile foundations. At 1x zoom the vertical slope edge is between two pixels, and the horizontal slope edge is in the middle of a pixel.

type

The type argument specifies which kind of sprite follows. This may be either BIT_DEPTH_8BPP or BIT_DEPTH_32BPP.

filename

Specifying a filename is optional, it's only useful if you have multiple sprites in the same file. If every sprite is in a separate file you'll have to specify the filename for each realsprite anyway, so you can leave it out of the alternative_sprites-block.

mask_filename

For 32bpp only, you can also specify a default filename to use for mask sprites. These (8bpp) sprites have the same size and offsets as the normal sprites and are used for recolouring purposes. See the real sprites page for more info.

Example

The block contains a list of real and/or recolour sprites. An example for an implementation

 // Foster Express tram
 spriteset(foster_express_set, "opengfx_generic_trams1.pcx") {
   [ 48,56,  8,18,   -3,-10]
   [ 64,56, 20,19,  -14, -5]
   [ 96,56, 28,15,  -14, -8]
   [144,56, 20,19,   -6, -7]
   [176,56,  8,18,   -3,-10]
   [192,56, 20,19,  -14, -9]
   [224,56, 28,15,  -14, -8]
   [272,56, 20,19,   -6, -7]
 }
 
 alternative_sprites(foster_express_set, ZOOM_LEVEL_IN_2X, BIT_DEPTH_8BPP, "opengfx_generic_trams1.pcx") {
   [ 48,56,  8,18,   -3,-10]
   [ 64,56, 20,19,  -14, -5]
   [ 96,56, 28,15,  -14, -8]
   [144,56, 20,19,   -6, -7]
   [176,56,  8,18,   -3,-10]
   [192,56, 20,19,  -14, -9]
   [224,56, 28,15,  -14, -8]
   [272,56, 20,19,   -6, -7]
 }
 
 alternative_sprites(foster_express_set, ZOOM_LEVEL_NORMAL, BIT_DEPTH_32BPP, "opengfx_generic_trams1.png") {
   [ 48,56,  8,18,   -3,-10]
   [ 64,56, 20,19,  -14, -5]
   [ 96,56, 28,15,  -14, -8]
   [144,56, 20,19,   -6, -7]
   [176,56,  8,18,   -3,-10]
   [192,56, 20,19,  -14, -9]
   [224,56, 28,15,  -14, -8]
   [272,56, 20,19,   -6, -7]
 }