MOHPA Guide To Global Lighting

This document serves to show the right way to use and manipulate global lighting in MOHPA missions.� In MOHPA terminology, �Global Lighting� refers to directional lights (also known as �infinite lights� such as the sun) or ambient lighting. You will also see how to move the global light to different positions via script or �Cvar� while a level is running.

Tuning

The following parameters make be set with Radiant �worldspawn� and additionally modified during game-play using �Cvars� (of the same name) or script commands.

Name:	Examples:	Description:
global_light_direction	( 90.0 0.0 )	The pitch and yaw angles (in degrees) for the direction the global light is pointing.� In this example it is pointing straight down.
global_light_color	( 255 0.0 0.0)	RGB values of the color of the directional light above. Values range from 0.0=black to 255=full-bright
global_light_ambientcolor	( 255 0.0 0.0)	RGB non-directional ambient light color. Values range from 0.0=black to 255=full-bright
global_light_ambientdirectionalcolor	( 255 0.0 0.0)	RGB of ambient light to use on objects in shadow. Values range from 0.0=black to 255=full-bright

Example I: Environmental

����� // This makes a guy look like he is walking through a glowing

����� // �lava� world

����� $world global_light_direction������ ( 0.0 -90.0 )

����� // Direction is �up�

����� $world global_light_color���������� ( 255 128 62 )

����� // Eerie orange

����� $world global_light_ambientcolor��� ( 0.0 0.0 0.0 )�

����� // No ambient light

Example II: Environmental

���� // This makes a guy look like a deer in the headlights

����� $world global_light_direction������ ( 0.0 45.0 )

����� // Direction is �up�

����� $world global_light_color���������� ( 255 255 255 )

����� // Eerie orange

����� $world global_light_ambientcolor �� ( 0.0 0.0 0.0 )�

����� // No ambient light

Example III:� A 90-second �Day�

����������� local.x������������������� = 1.0

������ local.x_inc��������� = 1.0/90.0

�����������������

������ // Ascending line on Y-axis(0.0-1.0) travelling from 1.0 to 0.0 on X-axis

������ // Descending line on Y-axis(1.0-0.0) travelling from 0.0 to -1.0 on X-axis

������ // Don�t worry I make it sinusoidal!

������ while(local.x > ( -1.0 ))

������ {

������������� if (local.x>0.0)

������������� ��� local.y�� = 1.0-local.x

������������� else

������������� ��� local.y = 1.0+local.x

�������������

������������� // Negate on local.y makes light shine �down�

������������� local.vector = ( 0.0 local.x -local.y )

�������������

������������� // "Normalize" gives us sin() and cos() since neither they or

������������� // "sqrt" exist in the scripting language

������������� local.vector = vector_normalize ( local.vector)

������������� local.vector = vector_toangles(local.vector)

������

������������� // Set the light direction

������������� $world global_light_direction���� ( local.vector[1] local.vector[2] )

���������������������������������

������������� local.x -= local.x_inc

��������������������

������������� waitframe

������ }

�����������