Uniforms

Uniforms that are declared in the code, are automatically added to the Uniforms view where they can be viewed and edited. Available built-in uniforms are listed here.

Uniforms Declaration

Uniforms are declared with the uniform keyword, with an optional default value assignment, and a //@uniform Line Annotation with more properties to customize the view.
Uniforms are global, and can be declared in multiple places, as long as the same type and default value (if not omitted) are used. To avoid duplication, the common sources could be used for shared uniforms declaration.

//@uniform, min: 0.0, max: 10.0, step: 0.1
uniform float blurSize = 1.0;

Uniforms Properties

To customize the way uniforms are being displayed and edited in the Uniforms view, the
//@uniform line annotation could be used with the following properties:

Common properties:

display-name:

The name that is displayed in the Uniforms view (string), if not provided, the uniform name is displayed with a default formatting (for example, “blurRadius1”, would be displayed as “Blur Radius 1”).

index:

Uniform order priority (integer).

Additional properties:

For int, float, vec#, ivec#, uvec# (without an underlying type specified):

min / max:

Value bounds (should be compatible with the uniform type).

step:

Value increment size (should be compatible with the uniform type).

Underlying types:

An underlying type can be specified with a type property (or with an annotation value), and can have one of the following values:

srgb / linear-rgb:

Available for vec3-4 uniforms.
When provided, a color picker is used for editing the value, with an alpha channel for vec4 uniforms. The type does not change the uniform value itself, only the way the color picker interprets it.
Note that if linear-rgb type is used, the color has to be converted back to srgb color space by the shader, before it could be displayed (see an example below).

position:

Available for vec2-3, ivec2-3, uvec2-3 uniforms, with optional min, max, step properties.
When provided, a graph is used for editing the position value, with the specified boundaries and step size.

normal:

Available for vec2-3.
When provided, a graph is used for editing the normal value.

Example

//@uniform, min: 0.0, max: vec2(5.0, 10.0), step: 0.1
uniform vec2 boxBlurSize = vec2(1.0, 2.0);

//@uniform: linear-rgb
uniform vec4 backgroundColor = vec4(1.0, 0.5, 0.0, 1.0);

void mainImage(out vec4 fragColor, in vec2 fragCoord)
{
    fragColor.rgb = backgroundColor; // read linear-rgb

    // ...

    // convert to srgb before displaying
    fragColor.rgb = vec3(pow(fragColor.r, 1.0 / 2.2), pow(fragColor.g, 1.0 / 2.2), pow(fragColor.b, 1.0 / 2.2));
}

Uniforms Group

Uniforms groups could be declared using the //@uniform-group line annotation, with the following properties:

name:

(required) Uniform group name (string).
When the same group name is declared in multiple sources, uniforms are merged to a single group in the Uniforms view.
The name can also be defined as an annotation value:
//@uniform-group: group-name.

display-name:

The name that is displayed in the Uniforms view (string), if not provided, the name property value is displayed with a default formatting (for example, “blurSettings1”, would be displayed as “Blur Settings 1”).

parent:

Name of a containing group (string), if not provided, the group is added to the root.

index:

Group order priority (integer).

Once a uniform group is declared, all the subsequent uniforms in the same file are automatically added to it. However, uniform groups are only nested if the parent property is specified.

Order

Uniforms are always placed before groups, both are ordered according to their index, and order of appearance in the code, where common sources come first, then Buffers, Image, and Viewers sources.
Negative indexes are relative to the end of the list, where -1 is last, -2 is second before last, and so on.

Storage

If not specified in the project definition, uniforms values are stored (on project save) by default alongside the project file, with a .uniforms.json suffix.
The uniforms values file is reloaded automatically when modified externally.