Defining an Environmental Effect

In this section, we ll show how to add a new environmental reverb effect to the predefined list. This new effect will be for the environment inside of a submarine .

The Submarine Project

There are very few steps needed to add a new environment. The first is perhaps the most difficult, in that you must come up with a define that matches the DSFXI3DL2Reverb structure listed previously. In dsound .h, you will find a list of these defines for the preset environments, as shown in the following example.

 #define I3DL2_ENVIRONMENT_PRESET_SEWERPIPE -1000,-1000, 0.0f, 2.81f, 0.14f,           429, 0.014f, 648, 0.021f, 80.0f, 60.0f, 5000.0f 

Follow these steps to create a submarine environment:

1. Create an I3DL2 definition for the environment. Chapter 5 and 7 will give you a lot of insight on these values, but for now, we will simply copy the sewer pipe environment and make it a submarine one. Add the following lines before the code for the envValues structure in  RumpusSFX.cpp .

    // Custom environment definitions.  #define I3DL2_ENVIRONMENT_SUBMARINE -1000,-1000, 0.0f, 2.81f, 0.14f,           429, 0.014f, 648, 0.021f, 80.0f, 60.0f, 5000.0f2. 

2. At the end of the envValues structure, add the define name into the structure.

    I3DL2_ENVIRONMENT_PRESET_SMALLROOM,      I3DL2_ENVIRONMENT_PRESET_MEDIUMROOM,      I3DL2_ENVIRONMENT_PRESET_LARGEROOM,      I3DL2_ENVIRONMENT_PRESET_MEDIUMHALL,      I3DL2_ENVIRONMENT_PRESET_LARGEHALL,      I3DL2_ENVIRONMENT_PRESET_PLATE,      I3DL2_ENVIRONMENT_SUBMARINE 

3. Change the value for max_environments in  RumpusSFX.h from 30 to 31.

4. Add the submarine name to the end of the Enames structure in  RumpusEnvironment.cpp .

    "Small room (music)",      "Medium room (music)",      "Large room (music)",      "Medium hall (music)",      "Large hall (music)",      "Plate (music)",      "Submarine" 

5. Compile and test the code. If there are any errors, double-check the previous steps.

You can add any number of new environments this way, since there is no limit.