//----------------------------------------------------------------------------
void ParticleSystems::CreateScene ()
{
mScene = new0 Node();
mWireState = new0 WireState();
mRenderer->SetOverrideWireState(mWireState);
VertexFormat* vformat = VertexFormat::Create(2,
VertexFormat::AU_POSITION, VertexFormat::AT_FLOAT3, 0,
VertexFormat::AU_TEXCOORD, VertexFormat::AT_FLOAT2, 0);
int vstride = vformat->GetStride();
const int numParticles = 32;
VertexBuffer* vbuffer = new0 VertexBuffer(4*numParticles, vstride);
Float4* positionSizes = new1<Float4>(numParticles);
for (int i = 0; i < numParticles; ++i)
{
positionSizes[i][0] = Mathf::SymmetricRandom();
positionSizes[i][1] = Mathf::SymmetricRandom();
positionSizes[i][2] = Mathf::SymmetricRandom();
positionSizes[i][3] = 0.25f*Mathf::UnitRandom();
}
Particles* particles = new0 Particles(vformat, vbuffer, sizeof(int),
positionSizes, 1.0f);
particles->AttachController(new0 BloodCellController());
mScene->AttachChild(particles);
// Create an image with transparency.
const int xsize = 32, ysize = 32;
Texture2D* texture = new0 Texture2D(Texture::TF_A8R8G8B8, xsize,
ysize, 1);
unsigned char* data = (unsigned char*)texture->GetData(0);
float factor = 1.0f/(xsize*xsize + ysize*ysize);
for (int y = 0, i = 0; y < ysize; ++y)
{
for (int x = 0; x < xsize; ++x)
{
// The image is red.
data[i++] = 0;
data[i++] = 0;
data[i++] = 255;
// Semitransparent within a disk, dropping off to zero outside the
// disk.
int dx = 2*x - xsize;
int dy = 2*y - ysize;
float value = factor*(dx*dx + dy*dy);
if (value < 0.125f)
{
value = Mathf::Cos(4.0f*Mathf::PI*value);
}
else
{
value = 0.0f;
}
data[i++] = (unsigned char)(255.0f*value);
}
}
Texture2DEffect* effect = new0 Texture2DEffect(Shader::SF_LINEAR);
effect->GetAlphaState(0, 0)->BlendEnabled = true;
effect->GetDepthState(0, 0)->Enabled = false;
particles->SetEffectInstance(effect->CreateInstance(texture));
}
//----------------------------------------------------------------------------
void BspNodes::CreateScene ()
{
// Create the scene graph.
//
// 1. The rectangles represent the BSP planes of the BSP tree. They
// share a VertexColor3Effect. You can see a plane from either side
// (backface culling disabled). The planes do not interfere with view
// of the solid objects (wirestate enabled).
//
// 2. The sphere, tetrahedron, and cube share a TextureEffect. These
// objects are convex. The backfacing triangles are discarded
// (backface culling enabled). The front facing triangles are drawn
// correctly by convexity, so depthbuffer reads are disabled and
// depthbuffer writes are enabled. The BSP-based sorting of objects
// guarantees that front faces of convex objects in the foreground
// are drawn after the front faces of convex objects in the background,
// which allows us to set the depthbuffer state as we have. That is,
// BSPNode sorts from back to front.
//
// 3. The torus has backface culling enabled and depth buffering enabled.
// This is necessary, because the torus is not convex.
//
// 4. Generally, if all objects are opaque, then you want to draw from
// front to back with depth buffering fully enabled. You need to
// reverse-order the elements of the visible set before drawing. If
// any of the objects are semitransparent, then drawing back to front
// is the correct order to handle transparency. However, you do not
// get the benefit of early z-rejection for opaque objects. A better
// BSP sorter needs to be built to produce a visible set with opaque
// objects listed first (front-to-back order) and semitransparent
// objects listed last (back-to-front order).
//
// scene
// ground
// bsp0
// bsp1
// bsp3
// torus
// rectangle3
// sphere
// rectangle1
// tetrahedron
// rectangle0
// bsp2
// cube
// rectangle2
// octahedron
mScene = new0 Node();
// Create the ground. It covers a square with vertices (1,1,0), (1,-1,0),
// (-1,1,0), and (-1,-1,0). Multiply the texture coordinates by a factor
// to enhance the wrap-around.
VertexFormat* vformat = VertexFormat::Create(2,
VertexFormat::AU_POSITION, VertexFormat::AT_FLOAT3, 0,
VertexFormat::AU_TEXCOORD, VertexFormat::AT_FLOAT2, 0);
StandardMesh sm(vformat);
VertexBufferAccessor vba;
TriMesh* ground = sm.Rectangle(2, 2, 16.0f, 16.0f);
vba.ApplyTo(ground);
for (int i = 0; i < vba.GetNumVertices(); ++i)
{
Float2& tcoord = vba.TCoord<Float2>(0, i);
tcoord[0] *= 128.0f;
tcoord[1] *= 128.0f;
}
std::string path = Environment::GetPathR("Horizontal.wmtf");
Texture2D* texture = Texture2D::LoadWMTF(path);
ground->SetEffectInstance(Texture2DEffect::CreateUniqueInstance(texture,
Shader::SF_LINEAR_LINEAR, Shader::SC_REPEAT, Shader::SC_REPEAT));
mScene->AttachChild(ground);
// Partition the region above the ground into 5 convex pieces. Each plane
// is perpendicular to the ground (not required generally).
VertexColor3Effect* vceffect = new0 VertexColor3Effect();
vceffect->GetCullState(0, 0)->Enabled = false;
vceffect->GetWireState(0, 0)->Enabled = true;
Vector2f v0(-1.0f, 1.0f);
Vector2f v1(1.0f, -1.0f);
Vector2f v2(-0.25f, 0.25f);
Vector2f v3(-1.0f, -1.0f);
Vector2f v4(0.0f, 0.0f);
Vector2f v5(1.0f, 0.5f);
Vector2f v6(-0.75f, -7.0f/12.0f);
Vector2f v7(-0.75f, 0.75f);
Vector2f v8(1.0f, 1.0f);
BspNode* bsp0 = CreateNode(v0, v1, vceffect, Float3(1.0f, 0.0f, 0.0f));
BspNode* bsp1 = CreateNode(v2, v3, vceffect, Float3(0.0f, 0.5f, 0.0f));
BspNode* bsp2 = CreateNode(v4, v5, vceffect, Float3(0.0f, 0.0f, 1.0f));
BspNode* bsp3 = CreateNode(v6, v7, vceffect, Float3(0.0f, 0.0f, 0.0f));
bsp0->AttachPositiveChild(bsp1);
bsp0->AttachNegativeChild(bsp2);
bsp1->AttachPositiveChild(bsp3);
// Attach an object in each convex region.
float height = 0.1f;
Vector2f center;
TriMesh* mesh;
// The texture effect for the convex objects.
Texture2DEffect* cvxeffect =
new0 Texture2DEffect(Shader::SF_LINEAR_LINEAR);
cvxeffect->GetDepthState(0, 0)->Enabled = false;
cvxeffect->GetDepthState(0, 0)->Writable = true;
// The texture effect for the torus.
Texture2DEffect* toreffect =
new0 Texture2DEffect(Shader::SF_LINEAR_LINEAR);
// The texture image shared by the objects.
path = Environment::GetPathR("Flower.wmtf");
texture = Texture2D::LoadWMTF(path);
// Region 0: Create a torus mesh.
mesh = sm.Torus(16, 16, 1.0f, 0.25f);
mesh->SetEffectInstance(toreffect->CreateInstance(texture));
mesh->LocalTransform.SetUniformScale(0.1f);
center = (v2 + v6 + v7)/3.0f;
mesh->LocalTransform.SetTranslate(APoint(center[0], center[1], height));
bsp3->AttachPositiveChild(mesh);
// Region 1: Create a sphere mesh.
mesh = sm.Sphere(32, 16, 1.0f);
mesh->SetEffectInstance(cvxeffect->CreateInstance(texture));
mesh->LocalTransform.SetUniformScale(0.1f);
center = (v0 + v3 + v6 + v7)/4.0f;
mesh->LocalTransform.SetTranslate(APoint(center[0], center[1], height));
bsp3->AttachNegativeChild(mesh);
// Region 2: Create a tetrahedron.
mesh = sm.Tetrahedron();
mesh->SetEffectInstance(cvxeffect->CreateInstance(texture));
mesh->LocalTransform.SetUniformScale(0.1f);
center = (v1 + v2 + v3)/3.0f;
mesh->LocalTransform.SetTranslate(APoint(center[0], center[1], height));
bsp1->AttachNegativeChild(mesh);
// Region 3: Create a hexahedron (cube).
mesh = sm.Hexahedron();
mesh->SetEffectInstance(cvxeffect->CreateInstance(texture));
mesh->LocalTransform.SetUniformScale(0.1f);
center = (v1 + v4 + v5)/3.0f;
mesh->LocalTransform.SetTranslate(APoint(center[0], center[1], height));
bsp2->AttachPositiveChild(mesh);
// Region 4: Create an octahedron.
mesh = sm.Octahedron();
mesh->SetEffectInstance(cvxeffect->CreateInstance(texture));
mesh->LocalTransform.SetUniformScale(0.1f);
center = (v0 + v4 + v5 + v8)/4.0f;
mesh->LocalTransform.SetTranslate(APoint(center[0], center[1], height));
bsp2->AttachNegativeChild(mesh);
mScene->AttachChild(bsp0);
}
