Material templates define inputs, constants, textures, shader states and the techniques that are being used by your materials. Material templates are quite dynamic and can be written in such a way that they are able to support multiple different but similar shaders. That means that you do not have to create a seperate template for each new shader you write if you have a well written template.
Remember that scrolling hud element shader we created within the introduction? The template we used was very basic and only supports 1 texture and uses a hard-coded techset. What if we want to use a second texture within a shader?
Example of a more dynamic template that can use 2 different techsets depending on your material settings in AssetManager:
#define HUD_SHADER_SUFFIX "2d_scroll_c0" // techset suffix for materials using this template
#define USE_SECOND_TEX 0 // default value if we only use a single colorMap
#define SECOND_TEX_PREFIX "c1" // the prefix we will add to our techset if using a second colorMap
// ---------------------
// check our current material
#if "$specColorMap$" != "" // check if the material uses a "specular map"
#define USE_SECOND_TEX 1 // set our "bool" to true if the material is using a second texture
// ---------------------
// set the techset used by the material
#if USE_SECOND_TEX
techniqueSet( HUD_SHADER_SUFFIX + SECOND_TEX_PREFIX ); // using a second texture so use techset "2d_scroll_c0c1"
#else
techniqueSet( HUD_SHADER_SUFFIX ); // otherwise use "2d_scroll_c0"
#endif
// ---------------------
// setup textures
#if "$colorMap$" == "" // check if the "colorMap" field in Asset Manager is empty
#error "missing specularMap! ( missing color map! )" // throw an error if it is
#else
// define the colorMap and assign related values set from within Asset Manager (@field_in_asset_manager@)
"colorMap" = streamable map( "@tileColor@", "@filterColor@", "$colorMap$", @nopicmipColor@ ) "@formatColor@" : "colorMap";
#endif
#if USE_SECOND_TEX
// we are going to use the specular map field as a second colorMap
"specularMap" = streamable map( "@tileColor@", "@filterColor@", "$specColorMap$", @nopicmipColor@ ) "@formatColor@" : "specularMap";
#endif
// ---------------------
// not really sure why we only reference the colorMap field here, but thats how its done
refImage( "$colorMap$" );The template will choose a fitting techset for your material settings set within Asset Manager.
Materials using only a single colorMap will be using the techset 2d_scroll_c0 while materials that use a second texture will use 2d_scroll_c0c1.
You obv. have to create 2 techsets now, each calling their own technique and each technique its own shaders.
Including other templates
#include "my_other_template.template"Using the custom-string field below the template field
#if "@customString@" != ""
#define MY_PREFIX "@customString@"
#else
#define MY_PREFIX ""
#endif
techniqueSet( "my_shader_desc_" + MY_PREFIX );Using constants
constantTable
{
// constants can be used for anything within the shader if you want some more customization options without modifying the shader itself
// you obv. have to pass them into your shader via your technique
"colorTint" = float4( @,colorTint@ );
"distortionScale" = float4( @distortionScaleX@, @distortionScaleY@, 0, 0 );
/*. . .*/
}Not using any texture at all
// you shader might not need any textures at all but you still need to reference an image
// now your template could look as simple as:
#include "commonsetup.template"
techniqueSet( "my_techset" );
refImage( "$white" ); // using a default texture