fragment
Use this entry point to change the color of a fragment after all other shading has been performed.
Declaration
static let fragment: SCNShaderModifierEntryPointDiscussion
Shader modifiers for this entry point execute in the fragment processing stage.
The fragment entry point defines the following structure:
struct SCNShaderOutput {
vec4 color;
} _output;Your shader modifier reads from this structure and writes a new color to the same structure to produce the final output color for each rendered fragment.
This shader modifier inverts the output color:
_output.color.rgb = vec3(1.0) - _output.color.rgb;