I've been able to spawn a trigger_multiple box in my map using sourcemod.
PHP Code:
//Create entity
int triggerbox = CreateEntityByName("trigger_multiple");
DispatchKeyValue(triggerbox, "spawnflags", "1");
SetEntityModel(triggerbox, MODEL_DEFAULT); // I don't understand why we need a model, but without it doesn't work
TeleportEntity(triggerbox, pos, NULL_VECTOR, NULL_VECTOR);
DispatchSpawn(triggerbox);
float fMins[3];
float fMaxs[3];
fMins[0] = -64.0 * 4.0;
fMins[1] = -64.0 * 4.0;
fMins[2] = -64.0 * 4.0;
fMaxs[0] = 64.0 * 8.0;
fMaxs[1] = 64.0 * 8.0;
fMaxs[2] = 64.0 * 8.0;
SetEntPropVector(triggerbox, Prop_Send, "m_vecMaxs", fMaxs);
SetEntPropVector(triggerbox, Prop_Send, "m_vecMins", fMins);
SetEntProp(triggerbox, Prop_Send, "m_nSolidType", 2);
new enteffects = GetEntProp(triggerbox, Prop_Send, "m_fEffects");
enteffects |= 32;
SetEntProp(triggerbox, Prop_Send, "m_fEffects", enteffects);
HookSingleEntityOutput(triggerbox, "OnStartTouch", EntOut_OnStartTouch);
Now I would like to add a material/texture to the box. So that when I run the console command "showtriggers_toggle" I can clearly see the boundaries of the trigger box. Also in the future, I might want to add just solid boxes with a specific material/texture.
SCREENSHOT
On the screenshot, the red arrow shows a trigger box that was already default inside the map. The green arrow points to a trigger box I know is there because the onStartTouch triggers correctly. I just can't see it as it doesn't have the correct material (or at least I assume that's the reason).