void ParticlePointRenderer::operator()(ParticleSystemNode* psys, FrameContext & context, const RenderParam & rp /* = 0 */) {
if ( (rp.getFlag(NO_GEOMETRY)) )
return;
// render particles
std::vector<Particle> & particles = psys->getParticles();
uint32_t count = psys->getParticleCount();
Rendering::VertexDescription vertexDesc;
const Rendering::VertexAttribute & posAttrib = vertexDesc.appendPosition3D();
const Rendering::VertexAttribute & colorAttrib = vertexDesc.appendColorRGBAByte();
// The usage of a cache for the mesh has been tested. Reusing a preallocated mesh is not faster.
Util::Reference<Rendering::Mesh> mesh = new Rendering::Mesh(vertexDesc, count, count);
mesh->setDataStrategy(Rendering::SimpleMeshDataStrategy::getPureLocalStrategy());
mesh->setDrawMode(Rendering::Mesh::DRAW_POINTS);
// mesh->setUseIndexData(false);
Rendering::MeshIndexData & indexData = mesh->openIndexData();
Rendering::MeshVertexData & vertexData = mesh->openVertexData();
Util::Reference<Rendering::PositionAttributeAccessor> positionAccessor = Rendering::PositionAttributeAccessor::create(vertexData, posAttrib.getNameId());
Util::Reference<Rendering::ColorAttributeAccessor> colorAccessor = Rendering::ColorAttributeAccessor::create(vertexData, colorAttrib.getNameId());
uint32_t * indices = indexData.data();
for(uint_fast32_t index = 0; index < count; ++index) {
const Particle & p = particles[index];
colorAccessor->setColor(index, p.color);
positionAccessor->setPosition(index, p.position);
*indices++ = index;
}
indexData.markAsChanged();
indexData.updateIndexRange();
vertexData.markAsChanged();
vertexData.updateBoundingBox();
context.displayMesh(mesh.get());
}
void ParticleBillboardRenderer::operator()(ParticleSystemNode * psys, FrameContext & context, const RenderParam & rp) {
if(rp.getFlag(NO_GEOMETRY)) {
return;
}
const auto & worldToCamera = context.getRenderingContext().getMatrix_worldToCamera();
const auto cameraToWorld = worldToCamera.inverse();
const auto halfRight = cameraToWorld.transformDirection(context.getWorldRightVector() * 0.5f);
const auto halfUp = cameraToWorld.transformDirection(context.getWorldUpVector() * 0.5f);
// 2. just update position for each particle and render
// render particles
const uint32_t count = psys->getParticleCount();
Rendering::VertexDescription vertexDesc;
const Rendering::VertexAttribute & posAttrib = vertexDesc.appendPosition3D();
const Rendering::VertexAttribute & colorAttrib = vertexDesc.appendColorRGBAByte();
const Rendering::VertexAttribute & texCoordAttrib = vertexDesc.appendTexCoord();
// The usage of a cache for the mesh has been tested. Reusing a preallocated mesh is not faster.
Util::Reference<Rendering::Mesh> mesh = new Rendering::Mesh(vertexDesc, 4 * count, 6 * count);
mesh->setDataStrategy(Rendering::SimpleMeshDataStrategy::getPureLocalStrategy());
Rendering::MeshIndexData & indexData = mesh->openIndexData();
Rendering::MeshVertexData & vertexData = mesh->openVertexData();
Util::Reference<Rendering::PositionAttributeAccessor> positionAccessor = Rendering::PositionAttributeAccessor::create(vertexData, posAttrib.getNameId());
Util::Reference<Rendering::ColorAttributeAccessor> colorAccessor = Rendering::ColorAttributeAccessor::create(vertexData, colorAttrib.getNameId());
Util::Reference<Rendering::TexCoordAttributeAccessor> texCoordAccessor = Rendering::TexCoordAttributeAccessor::create(vertexData, texCoordAttrib.getNameId());
uint32_t * indices = indexData.data();
uint_fast32_t index = 0;
for(const auto & p : psys->getParticles()) {
const Geometry::Vec3f upOffset = halfUp * p.size.getHeight();
const Geometry::Vec3f rightOffset = halfRight * p.size.getWidth();
colorAccessor->setColor(index + 0, p.color);
texCoordAccessor->setCoordinate(index + 0, Geometry::Vec2f(0.0f, 0.0f));
positionAccessor->setPosition(index + 0, p.position + upOffset - rightOffset);
colorAccessor->setColor(index + 1, p.color);
texCoordAccessor->setCoordinate(index + 1, Geometry::Vec2f(0.0f, 1.0f));
positionAccessor->setPosition(index + 1, p.position - upOffset - rightOffset);
colorAccessor->setColor(index + 2, p.color);
texCoordAccessor->setCoordinate(index + 2, Geometry::Vec2f(1.0f, 1.0f));
positionAccessor->setPosition(index + 2, p.position - upOffset + rightOffset);
colorAccessor->setColor(index + 3, p.color);
texCoordAccessor->setCoordinate(index + 3, Geometry::Vec2f(1.0f, 0.0f));
positionAccessor->setPosition(index + 3, p.position + upOffset + rightOffset);
*indices++ = index + 0;
*indices++ = index + 1;
*indices++ = index + 3;
*indices++ = index + 1;
*indices++ = index + 2;
*indices++ = index + 3;
index += 4;
}
indexData.markAsChanged();
indexData.updateIndexRange();
vertexData.markAsChanged();
vertexData.updateBoundingBox();
context.displayMesh(mesh.get());
}