Code: 3d_underwater_world/terrain.h

3D Underwater World (using OpenGL and SDL)

This is an example OpenGL SDL application which creates an animated 3D underwater world (screenshot), with "Thunderbird 4" with headlights moving on a spline path, a randomly generated sand terrain, sunken ship/submarine/treasure chest models, and swaying fish and seaweed. It is designed to demonstrate basic OpenGL features, and the structure is as follows:

global.h - Global constants

main.cpp - Main method

game.h game.cpp - Game class handling key presses, event loop and holding the World object.

world.h world.cpp - World class containing simulated enviroment with lighting setup, simulation functions and rendering code.

clipping.h clipping.cpp - contains the CameraView class holding the current camera position and orientation, and the FrustrumClipper class which uses hyperplanes to calculate whether a point is in view or not, so only objects inview are drawn.

primitives.h primitives.cpp - primitive functions for drawing simple geometric shapes, like quadrangles, and texturing them.

regulargrid.h regulargrid.cpp - contains a textured grid of elevations for use in the terrain

terrain.h terrain.cpp - generates a random fractal landscape using the diamond square function

splines.h splines.cpp - contains SplineCurve class and MotionPath class for holding a 3D path for an object to move along. The camera uses two, one for its position and one for its viewing object

textures.h textures.cpp - contains texture loading function, courtesy for John Carter and a Texture class to wrap common functionality.

vectors.h vectors.cpp - contains my own bespoke 3D vector class Vec3, 4D matrix class Mat4 (with transformation functions, and hyperplane class.

worldobjects.h worldobjects.cpp - holds base classes for world objects which contain class definitions and implementation of objects that are drawn and the animation functionality

seaweed.cpp - holds dynamic seaweed,
staticobjects.cpp - holds the submarine and the ship and the treausure chest,
vehicleobject.cpp - holds Thunderbird 4,
fish.cpp - holds fish objects

terrain.h

#include "regulargrid.h"

/*
* TerrainGrid class
* ----------------------
* Creates a random terrain using the 
* diamond-square fractal algorithm.
* -------------------------
* Tristan Aubrey-Jones 18/12/2007
*/

class TerrainGrid: public RegularGrid
{
      private:
              // height (as normals created in advance to create in
              // the unit square)
              float height;
              // roughness constant
              float roughness;
              // the dimension exponent e, where dimensions = (2^e,2^e)
              int e;
              // performs the square step of the diamond-square algorithm
              void performSquareStep(int sqrSize, RegularGridVertex ran);
              // peforms the diamond step of the diamond-square algorithm
              void performDiamondStep(int sqrSize, RegularGridVertex ran);
      public:
             // constructor
             // res - resolution exponent 
             // e.g. (1 gives 2x2, 8 gives 256x256)
             TerrainGrid(int res, float roughness, Vec3 v, Texture* tex): 
                 RegularGrid((2<