Hello,i had this problem in which the tree shader was looking good in the day but awful in the night,because of static values of ksAmbient and ksDiffuse. Now they can vary hour by hour. The only problem is that the change of values is instant and i dont know how to make smooth transition,despite using "lag"parameter. Anyway it's also ok like this. Here are the 2 files you need: Add these values in 'content/tracks/yourmap/extension/ext_config.ini' Code: [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD22/10 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0 VALUE_0_OFF=0 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD10/1030 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.3 VALUE_0_OFF=0.3 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD1030/11 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.4 VALUE_0_OFF=0.4 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD11/12 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.6 VALUE_0_OFF=0.6 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD12/13 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=1 VALUE_0_OFF=1 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD13/14 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=1 VALUE_0_OFF=1 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD14/15 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=1 VALUE_0_OFF=1 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD15/16 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=1 VALUE_0_OFF=1 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD16/19 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.9 VALUE_0_OFF=0.9 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD19/20 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.7 VALUE_0_OFF=0.7 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD20/21 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.5 VALUE_0_OFF=0.5 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 [MATERIAL_ADJUSTMENT_...] ACTIVE=1 CONDITION=TOD21/22 DESCRIPTION=trees KEY_0=ksAmbient VALUE_0=0.4 VALUE_0_OFF=0.4 KEY_1=ksDiffuse VALUE_1=0 VALUE_1_OFF=0 MATERIALS= trees1, trees2, trees3, trees4, trees5 LAG = 1 And create a file in assetto corsa/extension/config/tracks/yourtrack.ini Code: [CONDITION_70] ; active between 22-10 NAME=TOD22/10 INPUT=TIME LUT=(|0=1|36000=1|36000=0|79200=0|79200=1|86400=1|) [CONDITION_71] ; active between 10-10.30 NAME=TOD10/1030 INPUT=TIME LUT=(|0=0|36000=0|36000=1|37800=1|37800=0|86400=0|) [CONDITION_72] ; active between 10.30-11 NAME=TOD1030/11 INPUT=TIME LUT=(|0=0|37800=0|37800=1|39600=1|39600=0|86400=0|) [CONDITION_73] ; active between 11-12 NAME=TOD11/12 INPUT=TIME LUT=(|0=0|39600=0|39600=1|43200=1|43200=0|86400=0|) [CONDITION_74] ; active between 12–13 NAME=TOD12/13 INPUT=TIME LUT=(|0=0|43200=0|43200=1|46800=1|46800=0|86400=0|) [CONDITION_75] ; active between 13–14 NAME=TOD13/14 INPUT=TIME LUT=(|0=0|46800=0|46800=1|50400=1|50400=0|86400=0|) [CONDITION_76] ; active between 14–15 NAME=TOD14/15 INPUT=TIME LUT=(|0=0|50400=0|50400=1|54000=1|54000=0|86400=0|) [CONDITION_77] ; active between 15–16 NAME=TOD15/16 INPUT=TIME LUT=(|0=0|54000=0|54000=1|57600=1|57600=0|86400=0|) [CONDITION_78] ; active between 16–19 NAME=TOD16/19 INPUT=TIME LUT=(|0=0|57600=0|57600=1|68400=1|68400=0|86400=0|) [CONDITION_79] ; active between 19–20 NAME=TOD19/20 INPUT=TIME LUT=(|0=0|68400=0|68400=1|72000=1|72000=0|86400=0|) [CONDITION_80] ; active between 20-21 NAME=TOD20/21 INPUT=TIME LUT=(|0=0|72000=0|72000=1|75600=1|75600=0|86400=0|) [CONDITION_81] ; active between 21-22 NAME=TOD21/22 INPUT=TIME LUT=(|0=0|75600=0|75600=1|79200=1|79200=0|86400=0|) Now,the luminosity of the trees can vary every hour. You can change the hours in which the conditions are active,depends of the sunset and sunrise hours in your track. My track has sunrise at 10AM and sunset at 10PM.