//Version 2.0.0 (2025-04-03)
//Made by twitch.tv/Egglyberts (creator of Keysight)
//Integrates with Mask Mode Plus in Keysight to provide perfect semi-transparency
//Works best if implemented as two sources, with glow additive blended and geometry normal blended
//See guide for more info: https://egglyberts.live/keysight/wiki/guide_adv_mask_mode/

uniform bool Show_geometry = true;
uniform bool Show_glow = true;
uniform bool Use_opacity_on_glow = true;
uniform float Menu_opacity = 1.0;

float4 mainImage( VertData v_in ) : TARGET
{
//Threshold is halfway between multiply value in Keysight and 0.5
	float threshold = 0.4975;
	float mult = 0.495;
	float menu_pixels = 2.0;
	float4 raw = image.Sample(textureSampler, v_in.uv);
	float3 base = (raw.rgb);
	float mask;
	float alpha = 1.0;
	float add;

//Set additive mode bool as easy variable to call
	if(Use_opacity_on_glow == true)
		add = 0.0;
	else
		add = 1.0;

//This is dumb but hey, it works
	float4 menu_sample = image.Sample(textureSampler, uv_pixel_interval);
	float menu = menu_sample.r;

//Force point-sampling to avoid outlines due to masking resampling
	float2 intuv = (v_in.uv + (uv_pixel_interval * 0.5)) * (1/uv_pixel_interval);
	intuv = round(intuv);
	intuv = (intuv * uv_pixel_interval) - (uv_pixel_interval * 0.5);

//Remove the menu square by sampling adjacent to it for that little patch
	float2 menu_hide_uv;
	if((intuv.x <= (uv_pixel_interval.x * menu_pixels * 2.0)) && (intuv.y <= (uv_pixel_interval.y * menu_pixels * 2.0)))
		menu_hide_uv = (intuv + (uv_pixel_interval.x * menu_pixels * 2.0, uv_pixel_interval.y * menu_pixels));
	else
		menu_hide_uv = intuv;

	base = image.Sample(textureSampler, menu_hide_uv);

//Extract mask
	if(base.r >= threshold)
		mask = 0.0;
	else
		mask = 1.0;

//Bypass masking if menu is open
	if(menu >= 0.5)
		alpha = Menu_opacity;
	else
//Begin masking
	{
		base = base + (0.5 * mask);
		base = base - (0.5);
		base = base * (1 / mult);
	}

//Get max-brightness version
	float bright_alpha = max(base.r, max(base.g, base.b));
	bright_alpha = clamp(bright_alpha - mask, 0.0, 1.0);
	float pix_mult = 1.0/bright_alpha;
	float3 bright = base * pix_mult;

//Get glow with additive behaviour
	float3 glow = lerp(bright, base, add);

	if(Show_glow == false)
		glow = (glow * 0.0);

	bright_alpha = clamp((bright_alpha + add), 0.0, 1.0);
	if(Show_glow == false)
		bright_alpha = (bright_alpha * 0.0);

	glow = clamp(glow, 0.0, 1.0);

//Get geometry
	float3 geo = base * mask;
	geo = clamp(geo, 0.0, 1.0);
	if(Show_geometry == false)
		geo = geo * 0.0;

//Mix glow and geo
	float3 mix = (geo + glow);
	float final_alpha = (Show_geometry * mask) + bright_alpha;

//Do menu switching
	mix = lerp(mix, base, menu);
	final_alpha = lerp(final_alpha, Menu_opacity, menu);

	return float4(mix, (final_alpha));
}