Adding Support for Materials in Engine

Materials:

A material in my engine specifies which shaders a object has to use along with some material constants such as the color. Currently in my material i have support for Effects and colors but as you can see below, i also have support for specifying the textures, but support for textures will come at a later date.

[Update] I’ve removed the requirement to give the path to the binary file. So now the material file takes in just the path to the human-readable file. The filename changes from .effectbinary to .effect.

return
{
Material =
{
EffectLocation = "Effects/Effect1.Effect",
ConstantType = "float4",
ConstantName = "Color",
ConstantValue = {1,1,1,1},
TextureLocation = "Textures/Texture1.texture",
},
}

Similar to mesh builder and effect builder that we had before, I created a material builder, which takes in this file and outputs a binary file as shown below.

As you can see in the human-readable file above, I have a constant “color”, which can be specified in the file. If there is not value for the constant, i default it to white.

I then specify which material a gameobject has to use in the game. I have a material class which reads in the binary file into a material. To submit data from a material to shaders, we use a per material constant buffer. After performing this, we can now submit only meshes and material instead of mesh and effect.

The final result looks like this.

The reason we see black trees is because the constant color in that material is set to red which is {1,0,0,1}. The output color per fragment is calculated as

output color = vertexColor * material color;

Here vertexColor is green as it is using the same mesh as the other trees. So, we get {0,1,0,1} * {1,0,0,1}  which gives us {0,0,0,1} which is black.

After adding materials, now we sort the meshes first by effects and then by materials. Since all my meshes are using the same effect, they will now be sorted by materials as shown below.

 

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