// ---------------------------------------------------------------------
// Create an approximate mesh of the landscape.
//
void CRoamMeshDrawer::Tessellate(const float3& campos, int viewradius)
{
// Perform Tessellation
#ifdef _OPENMP
// hint: just helps a little with huge cpu usage in retessellation, still better than nothing
// _____
// |0|_|_|..
// |_|_|_|..
// |_|_|8|..
// .....
// split the patches in 3x3 sized blocks. The tessellation itself can
// extend into the neighbor patches (check Patch::Split). So we could
// not multi-thread the whole loop w/o mutexes (in ::Split).
// But instead we take a safety distance between the thread's working
// area (which is 2 patches), so they don't conflict with each other.
for (int idx = 0; idx < 9; ++idx) {
#pragma omp parallel for
for (int i = m_Patches.size() - 1; i >= 0; --i) {
Patch* it = &m_Patches[i];
const int X = it->m_WorldX;
const int Z = it->m_WorldY;
const int subindex = (X % 3) + (Z % 3) * 3;
if ((subindex == idx) && it->IsVisible()) {
it->Tessellate(campos, viewradius);
}
}
}
#else
for (std::vector<Patch>::iterator it = m_Patches.begin(); it != m_Patches.end(); ++it) {
if (it->IsVisible())
it->Tessellate(campos, viewradius);
}
#endif
}
// ---------------------------------------------------------------------
// Create an approximate mesh of the landscape.
//
bool CRoamMeshDrawer::Tessellate(const float3& campos, int viewradius)
{
// Perform Tessellation
// hint: threading just helps a little with huge cpu usage in retessellation, still better than nothing
// _____
// |0|_|_|..
// |_|_|_|..
// |_|_|8|..
// .....
// split the patches in 3x3 sized blocks. The tessellation itself can
// extend into the neighbor patches (check Patch::Split). So we could
// not multi-thread the whole loop w/o mutexes (in ::Split).
// But instead we take a safety distance between the thread's working
// area (which is 2 patches), so they don't conflict with each other.
bool forceTess = false;
for (int idx = 0; idx < 9; ++idx) {
for_mt(0, roamPatches.size(), [&](const int i){
Patch* it = &roamPatches[i];
const int X = it->m_WorldX;
const int Z = it->m_WorldY;
const int subindex = (X % 3) + (Z % 3) * 3;
if ((subindex == idx) && it->IsVisible()) {
if (!it->Tessellate(campos, viewradius))
forceTess = true;
}
});
if (forceTess)
return true;
}
return false;
}
/**
* Retessellates the current terrain
*/
void CRoamMeshDrawer::Update()
{
//FIXME this retessellates with the current camera frustum, shadow pass and others don't have to see the same patches!
//const CCamera* cam = (inShadowPass)? camera: cam2;
CCamera* cam = cam2;
// Update Patch visibility
Patch::UpdateVisibility(cam, m_Patches, numPatchesX);
// Check if a retessellation is needed
#define RETESSELLATE_MODE 1
bool retessellate = false;
{ //SCOPED_TIMER("ROAM::ComputeVariance");
for (int i = 0; i < (numPatchesX * numPatchesY); ++i) {
Patch& p = m_Patches[i];
#if (RETESSELLATE_MODE == 2)
if (p.IsVisible()) {
if (!visibilitygrid[i]) {
visibilitygrid[i] = true;
retessellate = true;
}
if (p.IsDirty()) {
//FIXME don't retessellate on small heightmap changes?
p.ComputeVariance();
retessellate = true;
}
} else {
visibilitygrid[i] = false;
}
#else
if (p.IsVisible() != visibilitygrid[i]) {
visibilitygrid[i] = p.IsVisible();
retessellate = true;
}
if (p.IsVisible() && p.IsDirty()) {
//FIXME don't retessellate on small heightmap changes?
p.ComputeVariance();
retessellate = true;
}
#endif
}
}
// Further conditions that can cause a retessellation
#if (RETESSELLATE_MODE == 2)
static const float maxCamDeltaDistSq = 500.0f * 500.0f;
retessellate |= ((cam->pos - lastCamPos).SqLength() > maxCamDeltaDistSq);
#endif
retessellate |= forceRetessellate;
retessellate |= (lastGroundDetail != smfGroundDrawer->GetGroundDetail());
// Retessellate
if (retessellate) {
{ //SCOPED_TIMER("ROAM::Tessellate");
//FIXME this tessellates with current camera + viewRadius
// so it doesn't retessellate patches that are e.g. only vis. in the shadow frustum
Reset();
Tessellate(cam->pos, smfGroundDrawer->GetGroundDetail());
}
{ //SCOPED_TIMER("ROAM::GenerateIndexArray");
#pragma omp parallel for
for (int i = m_Patches.size() - 1; i >= 0; --i) {
Patch* it = &m_Patches[i];
if (it->IsVisible()) {
it->GenerateIndices();
}
}
}
{ //SCOPED_TIMER("ROAM::Upload");
for (std::vector<Patch>::iterator it = m_Patches.begin(); it != m_Patches.end(); ++it) {
if (it->IsVisible()) {
it->Upload();
}
}
}
/*{
int tricount = 0;
for (std::vector<Patch>::iterator it = m_Patches.begin(); it != m_Patches.end(); it++) {
if (it->IsVisible()) {
tricount += it->GetTriCount();
}
}
LOG_L(L_DEBUG, "ROAM dbg: Framechange, fram=%i tris=%i, viewrad=%i, cd=%f, camera=(%5.0f, %5.0f, %5.0f) camera2= (%5.0f, %5.0f, %5.0f)",
globalRendering->drawFrame,
tricount,
smfGroundDrawer->viewRadius,
(cam->pos - lastCamPos).SqLength();,
camera->pos.x,
camera->pos.y,
camera->pos.z,
cam2->pos.x,
cam2->pos.y,
cam2->pos.z
);
}*/
lastGroundDetail = smfGroundDrawer->GetGroundDetail();
lastCamPos = cam->pos;
forceRetessellate = false;
}
}