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Occlusion: Check for light_propagates and do mapblock bounds checks

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SmallJoker committed Aug 17, 2019
1 parent 7d016b4 commit 6ada090bb05d9e6d5961a59f33ff6e104b44061a
Showing with 60 additions and 34 deletions.
  1. +5 −0 src/client/clientmap.cpp
  2. +52 −32 src/map.cpp
  3. +3 −2 src/map.h
@@ -151,6 +151,11 @@ void ClientMap::updateDrawList()
occlusion_culling_enabled = false;
}

// Uncomment to debug occluded blocks in the wireframe mode
// TODO: Include this as a flag for an extended debugging setting
//if (occlusion_culling_enabled && m_control.show_wireframe)
// occlusion_culling_enabled = porting::getTimeS() & 1;

for (const auto &sector_it : m_sectors) {
MapSector *sector = sector_it.second;
v2s16 sp = sector->getPos();
@@ -1032,21 +1032,46 @@ void Map::removeNodeTimer(v3s16 p)
block->m_node_timers.remove(p_rel);
}

bool Map::isOccluded(v3s16 pos_origin, v3s16 pos_blockcenter, float step,
float stepfac, float offset, float end_offset, u32 needed_count)
bool Map::isOccluded(const v3s16 &pos_camera, const v3s16 &pos_target,
const core::aabbox3d<s16> &block_bounds, float step, float stepfac, float offset,
u32 needed_count)
{
float distance = BS * pos_origin.getDistanceFrom(pos_blockcenter);
v3f direction = intToFloat(pos_blockcenter - pos_origin, BS);
direction.normalize();
v3f pos_origin_f = intToFloat(pos_origin, BS);
// Worst-case safety distance to keep to the target position
// Anything smaller than the mapblock diagonal could result in in self-occlusion
// Diagonal = sqrt(1*1 + 1*1 + 1*1)
const static float BLOCK_DIAGONAL = BS * MAP_BLOCKSIZE * 1.732f;

v3f direction = intToFloat(pos_target - pos_camera, BS);
float distance = direction.getLength();

// Disable occlusion culling for near mapblocks in underground
if (distance < BLOCK_DIAGONAL)
return false;

// Normalize direction vector
if (distance > 0.0f)
direction /= distance;

v3f pos_origin_f = intToFloat(pos_camera, BS);
u32 count = 0;
for (; offset < distance + end_offset; offset += step){
v3f pf = pos_origin_f + direction * offset;
v3s16 pos_node = floatToInt(pf, BS);
MapNode node = getNode(pos_node);
if (m_nodedef->get(node).drawtype == NDT_NORMAL) {
// not transparent, see ContentFeature::updateTextures
bool is_valid_position;

for (; offset < distance; offset += step) {
v3f pos_node_f = pos_origin_f + direction * offset;
v3s16 pos_node = floatToInt(pos_node_f, BS);

if (offset > distance - BLOCK_DIAGONAL) {
// Do accurate position checks:
// Check whether the node is inside the current mapblock
if (block_bounds.isPointInside(pos_node))
return false;
}

MapNode node = getNode(pos_node, &is_valid_position);

if (is_valid_position &&
!m_nodedef->get(node).light_propagates) {
// Cannot see through light-blocking nodes --> occluded
count++;
if (count >= needed_count)
return true;
@@ -1058,8 +1083,11 @@ bool Map::isOccluded(v3s16 pos_origin, v3s16 pos_blockcenter, float step,

bool Map::isBlockOccluded(MapBlock *block, v3s16 cam_pos_nodes)
{
// Check occlusion for center and all 8 corners of the mapblock
// Overshoot a little for less flickering
static const s16 bs2 = MAP_BLOCKSIZE / 2 + 1;
static const v3s16 dir8[8] = {
static const v3s16 dir9[9] = {
v3s16( 0, 0, 0),
v3s16( 1, 1, 1) * bs2,
v3s16( 1, 1, -1) * bs2,
v3s16( 1, -1, 1) * bs2,
@@ -1070,34 +1098,26 @@ bool Map::isBlockOccluded(MapBlock *block, v3s16 cam_pos_nodes)
v3s16(-1, -1, -1) * bs2,
};

v3s16 pos_blockcenter = block->getPos() * MAP_BLOCKSIZE;
pos_blockcenter += v3s16(MAP_BLOCKSIZE) / 2;
// Minimal and maximal positions in the mapblock
core::aabbox3d<s16> block_bounds = block->getBox();

float step = BS * 1;
v3s16 pos_blockcenter = block_bounds.MinEdge + (MAP_BLOCKSIZE / 2);

// Starting step size, value between 1m and sqrt(3)m
float step = BS * 1.2f;
// Multiply step by each iteraction by 'stepfac' to reduce checks in distance
float stepfac = 1.1;
float stepfac = 1.05f;

float start_offset = BS * 1;
// The occlusion search of 'isOccluded()' must stop short of the target
// point by distance 'end_offset' (end offset) to not enter the target mapblock.
// For the 8 mapblock corners 'end_offset' must therefore be the maximum diagonal
// of a mapblock, because we must consider all view angles.
// sqrt(1^2 + 1^2 + 1^2) = 1.732
float end_offset = -BS * MAP_BLOCKSIZE * 1.7321;
float start_offset = BS * 1.0f;

// to reduce the likelihood of falsely occluded blocks
// require at least two solid blocks
// this is a HACK, we should think of a more precise algorithm
u32 needed_count = 2;

// For the central point of the mapblock 'end_offset' can be halved
if (!isOccluded(cam_pos_nodes, pos_blockcenter,
step, stepfac, start_offset, end_offset / 2.0f, needed_count))
return false;

for (const v3s16 &dir : dir8) {
if (!isOccluded(cam_pos_nodes, pos_blockcenter + dir,
step, stepfac, start_offset, end_offset, needed_count))
for (const v3s16 &dir : dir9) {
if (!isOccluded(cam_pos_nodes, pos_blockcenter + dir, block_bounds,
step, stepfac, start_offset, needed_count))
return false;
}
return true;
@@ -310,8 +310,9 @@ class Map /*: public NodeContainer*/
// This stores the properties of the nodes on the map.
const NodeDefManager *m_nodedef;

bool isOccluded(v3s16 pos_origin, v3s16 pos_blockcenter, float step,
float stepfac, float start_offset, float end_offset, u32 needed_count);
bool isOccluded(const v3s16 &pos_camera, const v3s16 &pos_target,
const core::aabbox3d<s16> &block_bounds, float step, float stepfac,
float offset, u32 needed_count);

private:
f32 m_transforming_liquid_loop_count_multiplier = 1.0f;

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