question

In this sample model, I'm using code in the OnDraw trigger to adjust the color of the ambient light and light sources. The lights go up when the model starts and then go dark about 12 hours later, staying dark for the next 12 hours.

daylightdemo.fsm

It uses this code in the draw trigger:

Object current = ownerobject(c);
treenode view = param(1);

/**Adjust Light based off time of day*/

treenode viewSettings = view.find(">viewsettings");
treenode ambient = viewSettings.find("viewambient");
treenode lights = viewSettings.find("viewlights");

int secsPerDay = 60*60*24;
double percentDaylight = 3 * sin(2*pi() * ((time() % secsPerDay) / secsPerDay));
percentDaylight = min(1, max(0, percentDaylight));

for(int i = 1; i <= 3; i++)
	ambient.subnodes[i].value = 0.2 * percentDaylight;
	
for(int i = 1; i <= lights.subnodes.length; i++) {
	treenode light = lights.subnodes[i];
	double lightVal = 0.4 * percentDaylight;
	light.subnodes["viewlightr"].value = lightVal;
	light.subnodes["viewlightg"].value = lightVal;
	light.subnodes["viewlightb"].value = lightVal;
}