These optional parameters can be added to any background element.

trans = trans ; (optional) (string) Specifies the type of transparency blending to perform on the sprite. Transparency modes are default, none, add, sub. Respectively, these specify default behavior, no transparency, color addition and color subtraction. default and none both cause non-animated elements to be drawn without any transparency blending. For animated background elements, default will use anim-specific transparency while other values of trans will override the transparency flags in the anim. If add is specified, the alpha parameter may be used to control the blending. Defaults to default.

Note: If mugenversion is less than 1.0, none will behave the same as default for animated elements.

alpha = src_alpha,dst_alpha ; (optional) (int, int) Specifies the source and destination blend contributions when trans = add. Acceptable values are from 0 to 256. Defaults to 256,256.

id = id_number ; (int) This specifies an ID number for the background element. Multiple elements can share the same ID number. The purpose of the ID number is to allow background controllers to specify which elements they are operating on. Defaults to 0.

positionlink = link_flag ; (boolean) Set positionlink to 1 to lock this element's position to the position of the element immediately preceding it in the DEF file. If set to 1, the values of the start parameter for the current element are treated as an offset from the previous element's position. The delta parameter will have no effect in this case. This is useful for getting large groups of elements to move in unison; if you edit the start and delta values of the first element in the positionlink chain, the effects will be seen throughout all elements the chain. Defaults to 0.

windowdelta = window_dx,window_dy ; (float, float) Specifies the movement delta of the masking window. It works similarly to the delta parameter for the background element itself. Defaults to 0,0.

velocity = vel_x, vel_y ; (float, float) Specifies initial x- and y-velocities for the background element (these default to 0). This functionality is also subsumed by the VelSet background controller.

sin.x = amplitude, period, phase ; (float, float, float) Specifies sinusoidal movement for the element in the x-direction. The first parameter is the amplitude, the second parameter is the period of the motion in game ticks, and the third parameter specifies the initial phase shift of the sinusoidal motion (defaults to 0, i.e., the element will start in the exact middle of its sinusoidal range). This parameter is basically superseded by the SinX background controller.

sin.y = amplitude, period, phase ; (float, float, float) Works the same as the sin.x parameter, but in the y-direction.

(deprecated)
window = x1,y1,x2,y2 ; (int, int, int, int) This deprecated parameter is included for compatibility and the use of it is not guaranteed to work correctly under all cases of zooming. It specifies a masking window with coordinates relative to the top-right corner of the screen. The coordinates are endpoint inclusive.

1.1b and higher
maskwindow = x1,y1,x2,y2 ; (int, int, int, int) Specifies a masking window for the background element. A masking window is conceptually a rectangular box on the screen in which the sprite is contained. Any part of the sprite that lies outside of the box will not be drawn. x1,y1 specifies the coordinates of the top-left corner of the window, and x2,y2 specifies the coordinates of the bottom-right corner of the window. These coordinates are relative to the stage origin (top-middle of screen). These coordinates are "endpoint exclusive", i.e. the pixels along the bottom and right edges of the window will not be drawn. If omitted, window masking will not performed.

scalestart = scale_x, scale_y ; (float, float) Starting scale. Defaults to 1,1.

scaledelta = scale_dx, scale_dy ; (float, float) Similar to the delta parameter, this is the amount to change the scale of the element for each unit of camera movement. Defaults to 0,0.

zoomdelta = dzoom ; (float) Specifies the amount that the camera zoom affects the scale of the element. A value of 0 is means the element will not change size during zoom, and a value of 1 will scale the element by the same factor of camera zoom. Defaults to 1.