armorpaint/paint/sources/make_node_preview.ts

function make_node_preview_run(data: material_t, matcon: material_context_t, node: ui_node_t, group: ui_node_canvas_t, parents: ui_node_t[]): node_shader_context_t {
	let context_id: string = "mesh";
	let props: shader_context_t = {
		name: context_id,
		depth_write: false,
		compare_mode: "always",
		cull_mode: "clockwise",
		vertex_elements: [
			{
				name: "pos",
				data: "short4norm"
			},
			{
				name: "nor",
				data: "short2norm"
			},
			{
				name: "tex",
				data: "short2norm"
			},
			{
				name: "col",
				data: "short4norm"
			}
		],
		color_attachments: ["RGBA32"]
	};
	let con_mesh: node_shader_context_t = node_shader_context_create(data, props);

	con_mesh.allow_vcols = true;

	let kong: node_shader_t = node_shader_context_make_kong(con_mesh);

	node_shader_write_attrib_vert(kong, "output.pos = float4(input.pos.xy * 3.0, 0.0, 1.0);"); // Pos unpack
	node_shader_write_attrib_vert(kong, "var madd: float2 = float2(0.5, 0.5);");
	node_shader_add_out(kong, "tex_coord: float2");
	node_shader_write_attrib_vert(kong, "output.tex_coord = output.pos.xy * madd + madd;");
	node_shader_write_attrib_vert(kong, "output.tex_coord.y = 1.0 - output.tex_coord.y;");
	node_shader_write_attrib_frag(kong, "var tex_coord: float2 = input.tex_coord;");

	parser_material_init();
	parser_material_canvases = [context_raw.material.canvas];
	parser_material_nodes = context_raw.material.canvas.nodes;
	parser_material_links = context_raw.material.canvas.links;
	if (group != null) {
		parser_material_push_group(group);
		parser_material_parents = parents;
	}
	let links: ui_node_link_t[] = parser_material_links;
	let link: ui_node_link_t = {
		id: ui_next_link_id(links),
		from_id: node.id,
		from_socket: context_raw.node_preview_socket,
		to_id: -1,
		to_socket: -1
	};
	array_push(links, link);

	parser_material_con = con_mesh;
	parser_material_kong = kong;
	parser_material_matcon = matcon;

	parser_material_transform_color_space = false;
	let res: string = parser_material_write_result(link);
	parser_material_transform_color_space = true;
	let st: string = node.outputs[link.from_socket].type;
	if (st != "RGB" && st != "RGBA" && st != "VECTOR") {
		res = parser_material_to_vec3(res);
	}
	array_remove(links, link);

	kong.frag_out = "float4";
	node_shader_write_frag(kong, "var basecol: float3 = " + res + ";");
	node_shader_write_frag(kong, "output = float4(basecol.rgb, 1.0);");

	parser_material_finalize(con_mesh);

	con_mesh.data.shader_from_source = true;
	gpu_create_shaders_from_kong(node_shader_get(kong), ADDRESS(con_mesh.data.vertex_shader), ADDRESS(con_mesh.data.fragment_shader), ADDRESS(con_mesh.data._.vertex_shader_size), ADDRESS(con_mesh.data._.fragment_shader_size));

	return con_mesh;
}