Shader format

ShaderMania shaders are Metal fragment-style programs. Each shader provides a mainImage function that receives a mutable Data structure.

void mainImage(thread Data &data)
{
    float2 uv = data.uv;
    data.outColor = float4(uv.x, uv.y, 0.0, 1.0);
}

Incoming data

typedef struct
{
    float2              uv;         // UV coordinate 0..1
    float2              viewSize;   // Viewport size
    float2              fragCoord;  // uv * viewSize

    float               time;       // Global time in seconds
    unsigned int        frame;      // Frame number

    float4              outColor;   // Resulting RGBA color, default (0,0,0,1)

    texture2d<float>    slot0;      // Texture input slots
    texture2d<float>    slot1;
    texture2d<float>    slot2;
    texture2d<float>    slot3;
} Data;

Write the final shader color to data.outColor.

UI parameters

Parameter declarations create editable controls in ShaderMania. Parameter values are stored with the shader and reset when the parameter name changes. Up to 10 parameters per shader are supported.

Float slider

float size = ParamFloat<UI: "Slider", name: "Size", min: 0, max: 1, default: 0.8>

Color picker

float3 diskColor = ParamFloat3<UI: "Color", name: "Disk Color", default: #ffffff>

URL button

ShaderMania adds https:// automatically.

ParamUrl<name: "Watch Tutorial", url: "example.com/tutorial">

Texture inputs

Shaders can declare up to 4 named input slots.

texture2d<float> input = ParamInput<name: "Input Slot Name">

Sample from texture inputs with the provided helpers:

getLinearSample(texture2d<float>, float2 coord);
getNearestSample(texture2d<float>, float2 coord);

Example:

void mainImage(thread Data &data)
{
    float4 source = getLinearSample(data.slot0, data.uv);
    data.outColor = source;
}