corrected lighting bug where illuminant in front of the sun can take over the light level of the sun for a tile the illuminant occupies, ActorWithBody phys WIP

Former-commit-id: a1ce45eded6136464d0a2c02227c61ee8f2adcb2
Former-commit-id: e4af5a44eb79b4db85458c9233e43a6117797331

src/net/torvald/terrarum/ENVIRON.md

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+## Colour overlay ##
+
+Colour overlay is set to 6 500 K as untouched. The value must be
+
+* Increased when:
+    - Overcast (~ 7 000 K)
+    - Freezing area (~ 7 500 K)
+    
+* Decreased when:
+    - Tropical area (~ 5 500 K)
+    
+    
+## Sunlight ##
+
+Sunlight of the midday must have colour temperature of 5 700 K.