void TestApp::Run()
{
if (*mCore << "Config/T08.txt")
{
mCore->Lock();
// First we need to create a heightmap we'll use to create the terrain. R5 has a fairly flexible
// noise library with a variety of simple filters that we can use for just that purpose.
Noise noise;
// We want to generate a 256x256 heightmap
noise.SetSize(256, 256);
// You can combine a variety of filters to create the terrain's "final" look, but for the sake
// of simplicity, let's only use one -- a perlin noise. The numbers that follow are optional
// parameters. In this case '8' means generate an 8-octave noise, and 0.65 means that the noise
// with values above 0.65 will be mirrored, turning high peaks into volcano-like crevices.
// This type of noise is also known as ridged multifractal due to the ridges it tends to produce.
noise.ApplyFilter("Perlin").Set(8.0f, 0.65f);
// Now that we have our heightmap, we should create our terrain.
mTerrain = mCore->GetRoot()->AddObject<Terrain>("First Terrain");
// We want to partition our terrain into an 8 by 8 grid. This will create 64 subdivisions
// that the terrain will use together with frustum culling to automatically discard portions
// of the terrain that are not visible. We can actually see what percentage of the terrain
// is being rendered by using the Terrain::GetVisibility() function after the scene has been
// culled... but more on that later.
mTerrain->PartitionInto(8, 8);
// In order to fill the terrain's partitions with geometry we need to provide additional
// information about the heightmap that will be used and how it will be used to begin with.
// Terrain::Heightmap struct exists for just this purpose.
// Provide the heightmap itself
Terrain::Heightmap hm (noise.GetBuffer(), noise.GetWidth(), noise.GetHeight());
// We want each subdivided mesh to be 32 by 32 quads. As you might recall there are 64 subdivisions
// in total, and now each of those 64 will contain (32 x 32) = 1024 quads, or 2048 triangles.
// When the terrain is generated the provided heightmap will be sampled using bicubic filtering,
// so you can make the mesh much more tessellated than the heightmap, if you wish.
hm.mMeshSize.Set(32, 32);
// By default the terrain will be generated with dimensions of (0, 0, 0) to (1, 1, 1). Of course
// that's not what we want. Let's apply a different scaling property here, stretching the terrain
// along the horizontal plane (and a little bit along the vertical as well).
hm.mTerrainScale.Set(20.0f, 20.0f, 4.0f);
// By default the terrain starts at (0, 0, 0). Let's somwhat-center it instead.
hm.mTerrainOffset.Set(-10.0f, -10.0f, -3.0f);
// Time to fill the actual geometry. One last important thing to note is the optional bounding
// box padding parameter that QuadTree::Fill function accepts. This parameter is used to extrude
// the height of the bounding box vertically in both directions so that child objects can
// fit easier. Objects that "fit" into the bounding box of the terrain's subdivisioned
// nodes will get culled faster, speeding up your game. I recommend setting this property to
// the height of the tallest building or tree you expect to place on your map. In this
// example we don't have any objects placed as children of the terrain, but it's worth
// noting nonetheless.
mTerrain->FillGeometry(&hm, 0.0f);
// And now... we need to be able to see the terrain we've just created.
// The best way to visualize a terrain without any textures on it is to display it in wireframe.
// You can easily do that in R5 by using a material that has a "Wireframe" technique as one of
// its draw methods. As long as you won't forget to use that technique in the OnDraw function,
// your wireframe object will show up in your scene. In this case it will be used for our terrain.
// Wireframe is an R5-recognized technique so we don't need to set up any states.
ITechnique* wireframe = mGraphics->GetTechnique("Wireframe");
// Save it for our Draw function
//mTechniques.Expand() = wireframe;
// We'll be using a custom material to draw our terrain. Let's just give it the same name.
IMaterial* mat = mGraphics->GetMaterial("Terrain");
// Se need to change the material's color as all newly created materials start invisible (alpha of 0)
mat->SetDiffuse( Color4ub(255, 255, 255, 255) );
// Add this technique to the material
mat->GetDrawMethod(wireframe, true);
// Tell the terrain to use this material
mTerrain->SetMaterial(mat);
// Last thing we should do is find the label I've added to the "T08.txt" configuration file.
// The reason it's not created via code is to simplify this tutorial. If you're curious,
// have a look at that resource file and see how it was created inside. Since the label is
// part of the configuration file that we've loaded at the top of this function, it's already
// in memory and all we have to do is find it using this handy template:
mLabel = mUI->FindWidget<UILabel>("Status");
// Add a custom draw function that will update the label showing us how much of the terrain is
// actually visible at any given time. Look below to see exactly what it does.
mCore->AddOnDraw( bind(&TestApp::OnDraw, this) );
// Enter the message processing loop
mCore->Unlock();
while (mCore->Update());
//*mCore >> "Config/T08.txt";
}
}
