# PixelEffect:send

Available since LÖVE 0.8.0
This function is not supported in earlier versions.

Sends one or more values to a special (extern) variable inside the pixel effect. Extern variables have to be marked using the extern keyword, e.g.

    extern number time;
    extern vec2 light_pos;
    extern vec4 colors[4];

The corresponding send calls would be

    effect:send("time", t)
    effect:send("light_pos", {light_x, light_y})
    effect:send("colors", {r1, g1, b1, a1},  {r2, g2, b2, a2},  {r3, g3, b3, a3},  {r4, g4, b4, a4})

## Function

### Synopsis

    PixelEffect:send( name, number, ... )

### Arguments

`string name`
  Name of the number to send to the pixel effect.
`number number`
  Number to send to store in the extern.
`number ...`
  Additional numbers to send in case the extern is an array.

### Returns

Nothing.

### Returns

Nothing.

## Function

### Synopsis

    PixelEffect:send( name, vector, ... )

### Arguments

`string name`
  Name of the vector to send to the pixel effect.
`table vector`
  Numbers to send to the extern as a vector. The number of elements in the table determines the type of the vector (e.g. two numbers -> vec2). At least two and at most four numbers can be used.
`table ...`
  Additional vectors to send in case the extern is an array. All vectors need to be of the same size (e.g. only vec3's)

### Returns

Nothing.

## Function

### Synopsis

    PixelEffect:send( name, matrix, ... )

### Arguments

`string name`
  Name of the matrix to send to the pixel effect.
`table matrix`
  2x2, 3x3, or 4x4 matrix to send to the extern. Using table form: `{{a,b,c,d}, {e,f,g,h}, ... }`
`table ...`
  Additional matrices of the same type as matrix to store in the extern array.

### Returns

Nothing.

## Function

### Synopsis

    PixelEffect:send( name, image, ... )

### Arguments

`string name`
  Name of the Image to send to the pixel effect.
`Image image`
  Image to send to the extern.
`Image ...`
  Additional images in case the extern is an array.

### Returns

Nothing.

## Function

### Synopsis

    PixelEffect:send( name, canvas, ... )

### Arguments

`string name`
  Name of the Canvas to send to the pixel effect.
`Canvas canvas`
  Canvas to send to the extern. The pixel effect type is Image.
`Image ...`
  Additional canvases to send to the extern array.

### Returns

Nothing.

## See Also

- PixelEffect

##

Category:

- Functions