Virtual Ambient Light Textures

Edited by peter_spy, 2020

As of TDM 2.08 none of the below is needed, as TDM uses ambient lights to calculate this instead of textures. The option to switch between this and legacy system is no longer in the menu, but you can type tdm_ambient_method 0 in the game console to make sure you use the correct system.


OLD VERSION:
To improve performance on some low-end systems, Dark Mod textures can simulate the main ambient light. This feature pre-calculates how much textures should be illuminated once only instead of continuously. Players can select between three methods for ambient rendering, so those with faster machines can use the true ambient light which gives better quality.

So all textures should include these two stages:

Please note that there is also a command for automatically converting all materials to fulfill the TDM 1.03 requirements called tdm_batchConvertMaterials (see TDM Material Batch Conversion)

        // TDM Ambient Method Related
        {
                if (global5 == 1)
                blend add
                map                     textures/darkmod/yourname                         // Diffuse
                scale                   1, 1
                red                     global2
                green                   global3
                blue                    global4
        }
       

The first stage is for the simple ambient method, whereas the second one is for enhanced ambient rendering, which obviously also processes the normal- and specularmap of the material.

If a material does not contain a specularmap, the fragmentMap parameter 3 in the enhanced ambient rendering stage has to be changed to _black, e.g. "textures/darkmod/yourname_s" becomes "_black". If on the contrary a material does not contain a normalmap, the proper replacement is "_flat", meaning a flat surface, e.g. "textures/darkmod/yourname_local" becomes "_flat".

For vertex-blended materials, the ambient stages have to be altered in the following way:

        // TDM Ambient Method Related 
	{							
		if (global5 == 1)		
		blend add				
		map			textures/darkmod/materialA                         // Diffuse A
		scale			1, 1		
		red			global2	
		green			global3	
		blue			global4	
		vertexColor				
	}							
	{							
		if (global5 == 1)		
		blend add				
		map			textures/darkmod/materialB                         // Diffuse B
		scale			1, 1		
		red			global2	
		green			global3	
		blue			global4	
		inverseVertexColor		
	}							
	

AS OF TDM 2.0 the old Enhanced Ambient Stages:

{							
		if (global5 == 2)		
		blend add				
		program	ambientEnvVertexBlend.vfp	
		vertexParm		0		1, 1, 1, 1		          // UV Scales for Diffuse A and Bump A	resp.	
		vertexParm		1		1, 1, 1, 1		          // UV Scale for specular A and Diffuse B resp.
		vertexParm		2		1, 1, 1, 1		          // UV Scale for Bump B and specular B resp.	
		vertexParm		3		global2, global3, global4, 1	
		//----------- VertexColored -------------------			
		fragmentMap		0		cubeMap env/gen1				
		fragmentMap		1		textures/darkmod/materialA_local  // Bump A			
		fragmentMap		2		textures/darkmod/materialA	  // Diffuse A
		fragmentMap		3		textures/darkmod/materialA_s	  // Specular A		
		//----------- InverseVertexColored ------------			
		fragmentMap		4		textures/darkmod/materialB_local  // Bump B		
		fragmentMap		5		textures/darkmod/materialB	  // Diffuse B		
		fragmentMap		6		textures/darkmod/materialB_s	  // Specular B
	}

are no longer needed as the Ambient light now has it's own dedicated render path.