ddmyx/shaders/sh_flash/sh_flash.fsh

varying vec2 v_vTexcoord;
varying vec4 v_vColour;

uniform float f_alpha; 

void main()
{
    vec4 texColor = texture2D(gm_BaseTexture, v_vTexcoord);
    vec3 white = vec3(1.0, 1.0, 1.0);
    
    gl_FragColor = vec4(mix(texColor.rgb, white, f_alpha), texColor.a);
}