Terra additional lights

[Nickak2003]

So I have the terra directional light update working. Now I am trying to add additional lights how do I go about doing that? I tried just adding a point-light but it doesn't seem to light anything, terrain nor object.

[xrgo]

you need to enable forwardclustered (sceneManager->setForwardClustered)

[Nickak2003]

cool. What's the best way to determine the params for that call?

[xrgo]

mmm depends on your scene, how many lights, how big (range) how close, etc
What I did is test in my scene with most lights and just used very low values and started increasing them until I saw no gitches and I get good fps, and I use this for everything

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    forwardPlusParams[0] = 4; //width
    forwardPlusParams[1] = 4; //height
    forwardPlusParams[2] = 24; //numSlices
    forwardPlusParams[3] = 20; //lightsPerCell
    forwardPlusParams[4] = 0; //decalsPerCell
    forwardPlusParams[5] = 5; //cubemapProbesPerCel
    forwardPlusParams[6] = 5; //minDistance
    forwardPlusParams[7] = 500; //maxDistance

[Nickak2003]

How do I get the additional lights to cast shadows onto the terrain?

[xrgo]

casting shadow lights should just work (even without forwardclustered) call light->setCastShadows(true); and you need to set a compositor shadow node with enough shadow maps to handle them, see the PbsMaterials/shadowMapDebugging samples and its respective .compositor files

[Nickak2003]

Ok, thanks for your help, if you could bare with me =)

So I had the static shadow map tutorial implemented and working then I implemented terra and got that working, now, I tied to combine the two.
I added the shadow map code from the static shadows tutorial compostitor to the terra tutorial compositor. I'm not sure if that's what I was supposed to do or not.

I then added the code to setup the static shadow maps once terra's compositor has finished setting up.

The result is that the point light seems to have a different attenuation/range, more intense, and I do not get shadows from it. I do still get shadows from the directional light.

Heres's my terra compositor, which is just the two compositors combined:

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compositor_node Tutorial_TerrainRenderingNode
{
	in 0 rt_renderwindow
	in 1 TerraShadowTexture

	target rt_renderwindow
	{
		pass clear
		{
			colour_value 0.2 0.4 0.6 1
		}

		pass render_scene
		{
			load
			{
				all				clear
				clear_colour	0.2 0.4 0.6 1
			}
			store
			{
				colour	store_or_resolve
				depth	dont_care
				stencil	dont_care
			}

			expose TerraShadowTexture

			overlays	on
			shadows		Tutorial_TerrainShadowNode
		}
	}
}

compositor_node_shadow Tutorial_TerrainShadowNode
{
	technique pssm

	texture atlas 3072 2048 PFG_D32_FLOAT
	texture atlasStatic	4096 8192 PFG_D32_FLOAT
	texture tmpCubemap	1024 1024 PFG_R32_FLOAT cubemap depth_format PFG_D32_FLOAT

	num_splits		3
	pssm_lambda		0.95
	shadow_map 0 atlas uv 0.000000000000000 0.0 0.666666666666667 1.0 light 0 split 0
	shadow_map 1 atlas uv 0.666666666666667 0.0 0.333333333333333 0.5 light 0 split 1
	shadow_map 2 atlas uv 0.666666666666667 0.5 0.333333333333333 0.5 light 0 split 2

	technique focused
	shadow_map 3 atlasStatic uv 0.0 0.0 1.0 0.5 light 1
	shadow_map 4 atlasStatic uv 0.0 0.5 1.0 0.5 light 2

	target atlas
	{
		pass clear
		{
			colour_value 1 1 1 1
		}
	}

	shadow_map_target_type directional
	{
		shadow_map 0 1 2
		{
			pass render_scene
			{
			}
		}
	}


	//Clear the static atlas first. Do this inside a shadow_map_target_type block so that it only
	//gets executed if shadow_map 3 is flagged as dirty (instead of clearing every frame).
	shadow_map_target_type directional spot point
	{
		shadow_map 3
		{
			pass clear
			{
				clear_colour_reverse_depth_aware	1 1 1 1
				shadow_map_full_viewport yes
			}
		}
	}

	shadow_map_target_type point
	{
		shadow_map_repeat 3 4
		{
			target tmpCubemap +X : cubemap_target_shadow {}
			target tmpCubemap -X : cubemap_target_shadow {}
			target tmpCubemap +Y : cubemap_target_shadow {}
			target tmpCubemap -Y : cubemap_target_shadow {}
			target tmpCubemap +Z : cubemap_target_shadow {}
			target tmpCubemap -Z : cubemap_target_shadow {}

			shadow_map
			{
				pass render_quad
				{
					material Ogre/DPSM/CubeToDpsm
					input 0 tmpCubemap
				}
			}
		}
	}



}

workspace Tutorial_TerrainWorkspace
{
	connect_external 0 Tutorial_TerrainRenderingNode 0
	connect_external 1 Tutorial_TerrainRenderingNode 1
}

I noticed that there is a TerraShadowGenerator.compositor, I am unsure what that is.

On the c++ side I do all my normal terra stuff, except follow it up with this call, which is straight from the static maps tutorial:

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oid Graphics::setupShadows() {


    Ogre::Root* root = getRoot();
    Ogre::CompositorWorkspace* workspace = getWorkspace();
    Ogre::Hlms* hlmsUnlit = root->getHlmsManager()->getHlms(Ogre::HLMS_UNLIT);

    Ogre::HlmsMacroblock macroblock;
    macroblock.mDepthCheck = false;
    Ogre::HlmsBlendblock blendblock;

    Ogre::CompositorShadowNode* shadowNode =
        workspace->findShadowNode("Tutorial_TerrainShadowNode");
    const Ogre::CompositorShadowNodeDef* shadowNodeDef = shadowNode->getDefinition();
       
    for (int i = 0; i < 5; ++i){

        const Ogre::String datablockName("depthShadow" + Ogre::StringConverter::toString(i));
        Ogre::HlmsUnlitDatablock* depthShadow = (Ogre::HlmsUnlitDatablock*)hlmsUnlit->createDatablock(
            datablockName, datablockName,
            macroblock, blendblock,
            Ogre::HlmsParamVec());

        const Ogre::ShadowTextureDefinition* shadowTexDef =
            shadowNodeDef->getShadowTextureDefinition(i);

        Ogre::TextureGpu* tex = shadowNode->getDefinedTexture(shadowTexDef->getTextureNameStr());
        depthShadow->setTexture(0, tex);

        //If it's an UV atlas, then only display the relevant section.
        Ogre::Matrix4 uvOffsetScale;
        uvOffsetScale.makeTransform(Ogre::Vector3(shadowTexDef->uvOffset.x,
            shadowTexDef->uvOffset.y, 0.0f),
            Ogre::Vector3(shadowTexDef->uvLength.x,
                shadowTexDef->uvLength.y, 1.0f),
            Ogre::Quaternion::IDENTITY);
            
         

        depthShadow->setEnableAnimationMatrix(0, true);
        depthShadow->setAnimationMatrix(0, uvOffsetScale);
    }
}

I then assign the static map 3 to the point light, enable shadow casting from the light, and set it dirty each frame. Again, the light attenuation alters and there is no casted shadow.

Thanks for the help!

[Nickak2003]

OK, I figured it out, I forgot to add the cube map code to the compositor.
Was missing:

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abstract target cubemap_target_shadow
{
	pass render_scene
	{
		load
		{
			all                                 clear
			clear_colour_reverse_depth_aware	1 1 1 1
		}
		store
		{
			//We only care about the contents of the colour target with point shadows
			depth			dont_care
			stencil			dont_care
		}
		camera_cubemap_reorient true
	}
}