material.effect

If a certain technique does not work because the 3D hardware does not support the given texture stage states, the next technique from the effect is automatically selected. Therefore, an effect should always contain a simple fallback technique for supporting old hardware.

The effect string is compatible to the DirectX .fx format. The keywords used in the texture stage settings are basically the same used in the Microsoft DirectX 9c reference for texture and render states. Therefore, an effect can be written based on the microsoft documentation.

A reference list can be found in the DirectX9 documentation under DirectX Graphics -> Reference -> Effect Files Reference.

Remarks:

• Like every string constant, effect strings can consist of up to 10000 characters. Effect files have no size limit.
• Effects can be copied from another material during the first frame in a _startup function, like mtl.effect = mtl_envcube.effect; and can be reloaded at runtime through the effect_load instruction.
• Effect materials can be assigned to models, sprites and terrain and level geometrie.
• Effects are compiled at runtime into DirectX register states. Syntax errors will be indicated.
• Effects can use 4 skins from the model, plus 4 additional textures defined in the material. So every effect can use up to 8 textures.
• The rendering speed of an entity is reduced when an effect or a pixel or vertex shader is used. The more passes the effect performs and the more pixel shader instructions it contains, the slower is the rendering.

Edition

Example 1:

material mat_test
{
   effect = "shadertest.fx"; 
}

Example 2:

// the following code creates a material that adds DOT3 bumpmapping to a model
BMAP* reptile = "scales.tga";

material mat_bump
{
   skin2 = reptile; // set a reptile skin
   scale1 = 0.2; // factor for the skin scale at stage 0

   // define a material effect string
   effect = "

               // declare the used textures and variables
               texture entSkin1; // the entity skin
               texture mtlSkin2; // the bump map
               dword mtlSkill1;  // the light vector

               // default technique
               technique bump_dot3
               {
                  pass P0
                  {
                      // set texture stage states
                      Texture[0] = <mtlSkin2>;
                      Texture[1] = <entSkin1>;
                      TextureFactor = <mtlSkill1>;
  
                      ColorArg1[0] = Texture; // stage 0 = bumpmap
                      ColorOp[0] = DotProduct3;
                      ColorArg2[0] = TFactor;
  
                      ColorArg1[1] = Texture; // stage 1 - skin texture
                      ColorOp[1] = AddSigned;
                      ColorArg2[1] = Current;
  
                      ColorArg1[2] = Diffuse; // stage 2 - lighting
                      ColorOp[2] = Modulate2x;
                      ColorArg2[2] = Current;
                  }
               }

               // fallback technique for devices that do not support bumpmapping
               technique fallback
               {
                  pass P0
                  {
                     // set texture stage states
                     Texture[0] = <entSkin1>;
                     ColorArg1[0] = Texture; // stage 0 = skin texture
                     ColorOp[0] = Modulate2x;
                     ColorArg2[0] = Diffuse; // modulate by lighting
                  }
               }
             "; // end of the effect string
}


starter mat_bump_init 
{
   // initialize the material properties
   vec_set(mat_bump.ambient_blue,  mat_model.ambient_blue);
   vec_set(mat_bump.diffuse_blue,  mat_model.diffuse_blue);
   vec_set(mat_bump.specular_blue, mat_model.specular_blue);
   mat_bump.power = mat_model.power;
   // create the normals map for DOT3 bumpmapping
   bmap_to_normals(mat_bump.skin2,2);
   // set a lighting vector for DOT3 bumpmapping
   mat_bump.skill1 = pixel_for_vec(vector(200,200,200),100,8888);
}

See also:

Material, Effect, material.event, material.flags, material.matrix, effect_load