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1062 | /**************************************************************************/
/* visual_server_light_culler.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "visual_server_light_culler.h"
#include "core/math/camera_matrix.h"
#include "core/math/plane.h"
#include "scene/3d/camera.h"
#include "visual_server_globals.h"
#include "visual_server_scene.h"
#ifdef VISUAL_SERVER_LIGHT_CULLER_DEBUG_STRINGS
const char *VisualServerLightCuller::Data::string_planes[] = {
"NEAR",
"FAR",
"LEFT",
"TOP",
"RIGHT",
"BOTTOM",
};
const char *VisualServerLightCuller::Data::string_points[] = {
"FAR_LEFT_TOP",
"FAR_LEFT_BOTTOM",
"FAR_RIGHT_TOP",
"FAR_RIGHT_BOTTOM",
"NEAR_LEFT_TOP",
"NEAR_LEFT_BOTTOM",
"NEAR_RIGHT_TOP",
"NEAR_RIGHT_BOTTOM",
};
String VisualServerLightCuller::Data::plane_bitfield_to_string(unsigned int BF) {
String sz;
for (int n = 0; n < 6; n++) {
unsigned int bit = 1 << n;
if (BF & bit) {
sz += String(string_planes[n]) + ", ";
}
}
return sz;
}
#endif
bool VisualServerLightCuller::prepare_light(const VisualServerScene::Instance &p_instance) {
if (!data.is_active()) {
return true;
}
LightSource lsource;
switch (VSG::storage->light_get_type(p_instance.base)) {
case VS::LIGHT_SPOT:
lsource.type = LightSource::ST_SPOTLIGHT;
lsource.angle = VSG::storage->light_get_param(p_instance.base, VS::LIGHT_PARAM_SPOT_ANGLE);
lsource.range = VSG::storage->light_get_param(p_instance.base, VS::LIGHT_PARAM_RANGE);
break;
case VS::LIGHT_OMNI:
lsource.type = LightSource::ST_OMNI;
lsource.range = VSG::storage->light_get_param(p_instance.base, VS::LIGHT_PARAM_RANGE);
break;
case VS::LIGHT_DIRECTIONAL:
lsource.type = LightSource::ST_DIRECTIONAL;
// Could deal with a max directional shadow range here? NYI
// LIGHT_PARAM_SHADOW_MAX_DISTANCE
break;
}
lsource.pos = p_instance.transform.origin;
lsource.dir = -p_instance.transform.basis.get_axis(2);
lsource.dir.normalize();
bool visible = _add_light_camera_planes(lsource);
if (data.light_culling_active) {
return visible;
}
return true;
}
int VisualServerLightCuller::cull(int p_count, VisualServerScene::Instance **p_result_array) {
if (!data.is_active() || !is_caster_culling_active()) {
return p_count;
}
// If the light is out of range, no need to check anything, just return 0 casters.
// Ideally an out of range light should not even be drawn AT ALL (no shadow map, no PCF etc).
if (data.out_of_range) {
return 0;
}
int new_count = p_count;
// Go through all the casters in the list (the list will hopefully shrink as we go).
for (int n = 0; n < new_count; n++) {
// World space aabb.
const AABB &bb = p_result_array[n]->transformed_aabb;
#ifdef LIGHT_CULLER_DEBUG_LOGGING
if (is_logging()) {
print_line("bb : " + String(bb));
}
#endif
float r_min, r_max;
bool show = true;
for (int p = 0; p < data.num_cull_planes; p++) {
// As we only need r_min, could this be optimized?
bb.project_range_in_plane(data.cull_planes[p], r_min, r_max);
#ifdef LIGHT_CULLER_DEBUG_LOGGING
if (is_logging()) {
print_line("\tplane " + itos(p) + " : " + String(data.cull_planes[p]) + " r_min " + String(Variant(r_min)) + " r_max " + String(Variant(r_max)));
}
#endif
if (r_min > 0.0f) {
show = false;
break;
}
}
// Remove.
if (!show) {
// Quick unsorted remove - swap last element and reduce count.
p_result_array[n] = p_result_array[new_count - 1];
new_count--;
// Repeat this element next iteration of the loop as it has been removed and replaced by the last.
n--;
}
}
#ifdef LIGHT_CULLER_DEBUG_LOGGING
int removed = p_count - new_count;
if (removed) {
if (((data.debug_count) % 60) == 0) {
print_line("[" + itos(data.debug_count) + "] linear cull before " + itos(p_count) + " after " + itos(new_count));
}
}
#endif
return new_count;
}
void VisualServerLightCuller::add_cull_plane(const Plane &p) {
ERR_FAIL_COND(data.num_cull_planes >= MAX_CULL_PLANES);
data.cull_planes[data.num_cull_planes++] = p;
}
// Directional lights are different to points, as the origin is infinitely in the distance, so the plane third
// points are derived differently.
bool VisualServerLightCuller::add_light_camera_planes_directional(const LightSource &p_light_source) {
uint32_t lookup = 0;
// Directional light, we will use dot against the light direction to determine back facing planes.
for (int n = 0; n < 6; n++) {
float dot = data.frustum_planes[n].normal.dot(p_light_source.dir);
if (dot > 0.0f) {
lookup |= 1 << n;
// Add backfacing camera frustum planes.
add_cull_plane(data.frustum_planes[n]);
}
}
ERR_FAIL_COND_V(lookup >= LUT_SIZE, true);
// Deal with special case... if the light is INSIDE the view frustum (i.e. all planes face away)
// then we will add the camera frustum planes to clip the light volume .. there is no need to
// render shadow casters outside the frustum as shadows can never re-enter the frustum.
// Should never happen with directional light?? This may be able to be removed.
if (lookup == 63) {
data.num_cull_planes = 0;
for (int n = 0; n < data.frustum_planes.size(); n++) {
add_cull_plane(data.frustum_planes[n]);
}
return true;
}
// Each edge forms a plane.
#ifdef VISUAL_SERVER_LIGHT_CULLER_CALCULATE_LUT
const LocalVector<uint8_t> &entry = _calculated_LUT[lookup];
// each edge forms a plane
int n_edges = entry.size() - 1;
#else
uint8_t *entry = &data.LUT_entries[lookup][0];
int n_edges = data.LUT_entry_sizes[lookup] - 1;
#endif
for (int e = 0; e < n_edges; e++) {
int i0 = entry[e];
int i1 = entry[e + 1];
const Vector3 &pt0 = data.frustum_points[i0];
const Vector3 &pt1 = data.frustum_points[i1];
// Create a third point from the light direction.
Vector3 pt2 = pt0 - p_light_source.dir;
if (!_is_colinear_tri(pt0, pt1, pt2)) {
// Create plane from 3 points.
Plane p(pt0, pt1, pt2);
add_cull_plane(p);
}
}
// Last to 0 edge.
if (n_edges) {
int i0 = entry[n_edges]; // Last.
int i1 = entry[0]; // First.
const Vector3 &pt0 = data.frustum_points[i0];
const Vector3 &pt1 = data.frustum_points[i1];
// Create a third point from the light direction.
Vector3 pt2 = pt0 - p_light_source.dir;
if (!_is_colinear_tri(pt0, pt1, pt2)) {
// Create plane from 3 points.
Plane p(pt0, pt1, pt2);
add_cull_plane(p);
}
}
#ifdef LIGHT_CULLER_DEBUG_LOGGING
if (is_logging()) {
print_line("lcam.pos is " + String(p_light_source.pos));
}
#endif
return true;
}
bool VisualServerLightCuller::_add_light_camera_planes(const LightSource &p_light_source) {
if (!data.is_active()) {
return true;
}
// We should have called prepare_camera before this.
ERR_FAIL_COND_V(data.frustum_planes.size() != 6, true);
// Start with 0 cull planes.
data.num_cull_planes = 0;
data.out_of_range = false;
switch (p_light_source.type) {
case LightSource::ST_SPOTLIGHT:
case LightSource::ST_OMNI:
break;
case LightSource::ST_DIRECTIONAL:
return add_light_camera_planes_directional(p_light_source);
break;
default:
return false; // not yet supported
break;
}
uint32_t lookup = 0;
// Find which of the camera planes are facing away from the light.
// We can also test for the situation where the light max range means it cannot
// affect the camera frustum. This is absolutely worth doing because it is relatively
// cheap, and if the entire light can be culled this can vastly improve performance
// (much more than just culling casters).
// POINT LIGHT (spotlight, omni)
// Instead of using dot product to compare light direction to plane, we can simply
// find out which side of the plane the camera is on. By definition this marks the point at which the plane
// becomes invisible.
// OMNIS
if (p_light_source.type == LightSource::ST_OMNI) {
for (int n = 0; n < 6; n++) {
float dist = data.frustum_planes[n].distance_to(p_light_source.pos);
if (dist < 0.0f) {
lookup |= 1 << n;
// Add backfacing camera frustum planes.
add_cull_plane(data.frustum_planes[n]);
} else {
// Is the light out of range?
// This is one of the tests. If the point source is more than range distance from a frustum plane, it can't
// be seen.
if (dist >= p_light_source.range) {
// If the light is out of range, no need to do anything else, everything will be culled.
data.out_of_range = true;
return false;
}
}
}
} else {
// SPOTLIGHTs, more complex to cull.
Vector3 pos_end = p_light_source.pos + (p_light_source.dir * p_light_source.range);
// This is the radius of the cone at distance 1.
float radius_at_dist_one = Math::tan(Math::deg2rad(p_light_source.angle));
// The worst case radius of the cone at the end point can be calculated
// (the radius will scale linearly with length along the cone).
float end_cone_radius = radius_at_dist_one * p_light_source.range;
for (int n = 0; n < 6; n++) {
float dist = data.frustum_planes[n].distance_to(p_light_source.pos);
if (dist < 0.0f) {
// Either the plane is backfacing or we are inside the frustum.
lookup |= 1 << n;
// Add backfacing camera frustum planes.
add_cull_plane(data.frustum_planes[n]);
} else {
// The light is in front of the plane.
// Is the light out of range?
if (dist >= p_light_source.range) {
data.out_of_range = true;
return false;
}
// For a spotlight, we can use an extra test
// at this point the cone start is in front of the plane...
// If the cone end point is further than the maximum possible distance to the plane
// we can guarantee that the cone does not cross the plane, and hence the cone
// is outside the frustum.
float dist_end = data.frustum_planes[n].distance_to(pos_end);
if (dist_end >= end_cone_radius) {
data.out_of_range = true;
return false;
}
}
}
}
// The lookup should be within the LUT, logic should prevent this.
ERR_FAIL_COND_V(lookup >= LUT_SIZE, true);
// Deal with special case... if the light is INSIDE the view frustum (i.e. all planes face away)
// then we will add the camera frustum planes to clip the light volume .. there is no need to
// render shadow casters outside the frustum as shadows can never re-enter the frustum.
if (lookup == 63) {
data.num_cull_planes = 0;
for (int n = 0; n < data.frustum_planes.size(); n++) {
add_cull_plane(data.frustum_planes[n]);
}
return true;
}
// Each edge forms a plane.
uint8_t *entry = &data.LUT_entries[lookup][0];
int n_edges = data.LUT_entry_sizes[lookup] - 1;
const Vector3 &pt2 = p_light_source.pos;
for (int e = 0; e < n_edges; e++) {
int i0 = entry[e];
int i1 = entry[e + 1];
const Vector3 &pt0 = data.frustum_points[i0];
const Vector3 &pt1 = data.frustum_points[i1];
if (!_is_colinear_tri(pt0, pt1, pt2)) {
// Create plane from 3 points.
Plane p(pt0, pt1, pt2);
add_cull_plane(p);
}
}
// Last to 0 edge.
if (n_edges) {
int i0 = entry[n_edges]; // Last.
int i1 = entry[0]; // First.
const Vector3 &pt0 = data.frustum_points[i0];
const Vector3 &pt1 = data.frustum_points[i1];
if (!_is_colinear_tri(pt0, pt1, pt2)) {
// Create plane from 3 points.
Plane p(pt0, pt1, pt2);
add_cull_plane(p);
}
}
#ifdef LIGHT_CULLER_DEBUG_LOGGING
if (is_logging()) {
print_line("lsource.pos is " + String(p_light_source.pos));
}
#endif
return true;
}
bool VisualServerLightCuller::prepare_camera(const Transform &p_cam_transform, const CameraMatrix &p_cam_matrix) {
data.debug_count++;
// For debug flash off and on.
#ifdef LIGHT_CULLER_DEBUG_FLASH
if (!Engine::get_singleton()->is_editor_hint()) {
int dc = data.debug_count / LIGHT_CULLER_DEBUG_FLASH_FREQUENCY;
bool bnew_active;
bnew_active = (dc % 2) == 0;
if (bnew_active != data.active) {
data.active = bnew_active;
print_line("switching light culler " + String(Variant(data.active)));
}
}
#endif
if (!data.is_active()) {
return false;
}
// Get the camera frustum planes in world space.
data.frustum_planes = p_cam_matrix.get_projection_planes(p_cam_transform);
data.num_cull_planes = 0;
#ifdef LIGHT_CULLER_DEBUG_LOGGING
if (is_logging()) {
for (int p = 0; p < 6; p++) {
print_line("plane " + itos(p) + " : " + String(data.frustum_planes[p]));
}
}
#endif
// We want to calculate the frustum corners in a specific order.
const CameraMatrix::Planes intersections[8][3] = {
{ CameraMatrix::PLANE_FAR, CameraMatrix::PLANE_LEFT, CameraMatrix::PLANE_TOP },
{ CameraMatrix::PLANE_FAR, CameraMatrix::PLANE_LEFT, CameraMatrix::PLANE_BOTTOM },
{ CameraMatrix::PLANE_FAR, CameraMatrix::PLANE_RIGHT, CameraMatrix::PLANE_TOP },
{ CameraMatrix::PLANE_FAR, CameraMatrix::PLANE_RIGHT, CameraMatrix::PLANE_BOTTOM },
{ CameraMatrix::PLANE_NEAR, CameraMatrix::PLANE_LEFT, CameraMatrix::PLANE_TOP },
{ CameraMatrix::PLANE_NEAR, CameraMatrix::PLANE_LEFT, CameraMatrix::PLANE_BOTTOM },
{ CameraMatrix::PLANE_NEAR, CameraMatrix::PLANE_RIGHT, CameraMatrix::PLANE_TOP },
{ CameraMatrix::PLANE_NEAR, CameraMatrix::PLANE_RIGHT, CameraMatrix::PLANE_BOTTOM },
};
for (int i = 0; i < 8; i++) {
// 3 plane intersection, gives us a point.
bool res = data.frustum_planes[intersections[i][0]].intersect_3(data.frustum_planes[intersections[i][1]], data.frustum_planes[intersections[i][2]], &data.frustum_points[i]);
// What happens with a zero frustum? NYI - deal with this.
ERR_FAIL_COND_V(!res, false);
#ifdef LIGHT_CULLER_DEBUG_LOGGING
if (is_logging()) {
print_line("point " + itos(i) + " -> " + String(data.frustum_points[i]));
}
#endif
}
return true;
}
VisualServerLightCuller::VisualServerLightCuller() {
// Used to determine which frame to give debug output.
data.debug_count = -1;
// bactive is switching on and off the light culler
data.caster_culling_active = Engine::get_singleton()->is_editor_hint() == false;
#ifdef VISUAL_SERVER_LIGHT_CULLER_CALCULATE_LUT
create_LUT();
#endif
}
/* clang-format off */
uint8_t VisualServerLightCuller::Data::LUT_entry_sizes[LUT_SIZE] = {0, 4, 4, 0, 4, 6, 6, 8, 4, 6, 6, 8, 6, 6, 6, 6, 4, 6, 6, 8, 0, 8, 8, 0, 6, 6, 6, 6, 8, 6, 6, 4, 4, 6, 6, 8, 6, 6, 6, 6, 0, 8, 8, 0, 8, 6, 6, 4, 6, 6, 6, 6, 8, 6, 6, 4, 8, 6, 6, 4, 0, 4, 4, 0, };
// The lookup table used to determine which edges form the silhouette of the camera frustum,
// depending on the viewing angle (defined by which camera planes are backward facing).
uint8_t VisualServerLightCuller::Data::LUT_entries[LUT_SIZE][8] = {
{0, 0, 0, 0, 0, 0, 0, 0, },
{7, 6, 4, 5, 0, 0, 0, 0, },
{1, 0, 2, 3, 0, 0, 0, 0, },
{0, 0, 0, 0, 0, 0, 0, 0, },
{1, 5, 4, 0, 0, 0, 0, 0, },
{1, 5, 7, 6, 4, 0, 0, 0, },
{4, 0, 2, 3, 1, 5, 0, 0, },
{5, 7, 6, 4, 0, 2, 3, 1, },
{0, 4, 6, 2, 0, 0, 0, 0, },
{0, 4, 5, 7, 6, 2, 0, 0, },
{6, 2, 3, 1, 0, 4, 0, 0, },
{2, 3, 1, 0, 4, 5, 7, 6, },
{0, 1, 5, 4, 6, 2, 0, 0, },
{0, 1, 5, 7, 6, 2, 0, 0, },
{6, 2, 3, 1, 5, 4, 0, 0, },
{2, 3, 1, 5, 7, 6, 0, 0, },
{2, 6, 7, 3, 0, 0, 0, 0, },
{2, 6, 4, 5, 7, 3, 0, 0, },
{7, 3, 1, 0, 2, 6, 0, 0, },
{3, 1, 0, 2, 6, 4, 5, 7, },
{0, 0, 0, 0, 0, 0, 0, 0, },
{2, 6, 4, 0, 1, 5, 7, 3, },
{7, 3, 1, 5, 4, 0, 2, 6, },
{0, 0, 0, 0, 0, 0, 0, 0, },
{2, 0, 4, 6, 7, 3, 0, 0, },
{2, 0, 4, 5, 7, 3, 0, 0, },
{7, 3, 1, 0, 4, 6, 0, 0, },
{3, 1, 0, 4, 5, 7, 0, 0, },
{2, 0, 1, 5, 4, 6, 7, 3, },
{2, 0, 1, 5, 7, 3, 0, 0, },
{7, 3, 1, 5, 4, 6, 0, 0, },
{3, 1, 5, 7, 0, 0, 0, 0, },
{3, 7, 5, 1, 0, 0, 0, 0, },
{3, 7, 6, 4, 5, 1, 0, 0, },
{5, 1, 0, 2, 3, 7, 0, 0, },
{7, 6, 4, 5, 1, 0, 2, 3, },
{3, 7, 5, 4, 0, 1, 0, 0, },
{3, 7, 6, 4, 0, 1, 0, 0, },
{5, 4, 0, 2, 3, 7, 0, 0, },
{7, 6, 4, 0, 2, 3, 0, 0, },
{0, 0, 0, 0, 0, 0, 0, 0, },
{3, 7, 6, 2, 0, 4, 5, 1, },
{5, 1, 0, 4, 6, 2, 3, 7, },
{0, 0, 0, 0, 0, 0, 0, 0, },
{3, 7, 5, 4, 6, 2, 0, 1, },
{3, 7, 6, 2, 0, 1, 0, 0, },
{5, 4, 6, 2, 3, 7, 0, 0, },
{7, 6, 2, 3, 0, 0, 0, 0, },
{3, 2, 6, 7, 5, 1, 0, 0, },
{3, 2, 6, 4, 5, 1, 0, 0, },
{5, 1, 0, 2, 6, 7, 0, 0, },
{1, 0, 2, 6, 4, 5, 0, 0, },
{3, 2, 6, 7, 5, 4, 0, 1, },
{3, 2, 6, 4, 0, 1, 0, 0, },
{5, 4, 0, 2, 6, 7, 0, 0, },
{6, 4, 0, 2, 0, 0, 0, 0, },
{3, 2, 0, 4, 6, 7, 5, 1, },
{3, 2, 0, 4, 5, 1, 0, 0, },
{5, 1, 0, 4, 6, 7, 0, 0, },
{1, 0, 4, 5, 0, 0, 0, 0, },
{0, 0, 0, 0, 0, 0, 0, 0, },
{3, 2, 0, 1, 0, 0, 0, 0, },
{5, 4, 6, 7, 0, 0, 0, 0, },
{0, 0, 0, 0, 0, 0, 0, 0, },
};
/* clang-format on */
#ifdef VISUAL_SERVER_LIGHT_CULLER_CALCULATE_LUT
// See e.g. http://lspiroengine.com/?p=153 for reference.
// Principles are the same, but differences to the article:
// * Order of planes / points is different in Godot.
// * We use a lookup table at runtime.
void VisualServerLightCuller::create_LUT() {
// Each pair of planes that are opposite can have an edge.
for (int plane_0 = 0; plane_0 < PLANE_TOTAL; plane_0++) {
// For each neighbour of the plane.
PlaneOrder neighs[4];
get_neighbouring_planes((PlaneOrder)plane_0, neighs);
for (int n = 0; n < 4; n++) {
int plane_1 = neighs[n];
// If these are opposite we need to add the 2 points they share.
PointOrder pts[2];
get_corners_of_planes((PlaneOrder)plane_0, (PlaneOrder)plane_1, pts);
add_LUT(plane_0, plane_1, pts);
}
}
for (uint32_t n = 0; n < LUT_SIZE; n++) {
compact_LUT_entry(n);
}
debug_print_LUT();
debug_print_LUT_as_table();
}
// we can pre-create the entire LUT and store it hard coded as a static inside the executable!
// it is only small in size, 64 entries with max 8 bytes per entry
void VisualServerLightCuller::debug_print_LUT_as_table() {
print_line("\nLIGHT VOLUME TABLE BEGIN\n");
print_line("Copy this to LUT_entry_sizes:\n");
String sz = "{";<--- Shadowed declaration
for (int n = 0; n < LUT_SIZE; n++) {
const LocalVector<uint8_t> &entry = _calculated_LUT[n];
sz += itos(entry.size()) + ", ";
}
sz += "}";
print_line(sz);
print_line("\nCopy this to LUT_entries:\n");
for (int n = 0; n < LUT_SIZE; n++) {
const LocalVector<uint8_t> &entry = _calculated_LUT[n];
String sz = "{";<--- Shadow variable
// First is the number of points in the entry.
int s = entry.size();
for (int p = 0; p < 8; p++) {
if (p < s)
sz += itos(entry[p]);
else
sz += "0"; // just a spacer
sz += ", ";
}
sz += "},";
print_line(sz);
}
print_line("\nLIGHT VOLUME TABLE END\n");
}
void VisualServerLightCuller::debug_print_LUT() {
for (uint32_t n = 0; n < LUT_SIZE; n++) {
String sz;
sz = "LUT" + itos(n) + ":\t";
sz += Data::plane_bitfield_to_string(n);
print_line(sz);
const LocalVector<uint8_t> &entry = _calculated_LUT[n];
sz = "\t" + string_LUT_entry(entry);
print_line(sz);
}
}
String VisualServerLightCuller::string_LUT_entry(const LocalVector<uint8_t> &p_entry) {
String string;
for (uint32_t n = 0; n < p_entry.size(); n++) {
uint8_t val = p_entry[n];
DEV_ASSERT(val < 8);
const char *sz_point = Data::string_points[val];
string += sz_point;
string += ", ";
}
return string;
}
String VisualServerLightCuller::debug_string_LUT_entry(const LocalVector<uint8_t> &p_entry, bool p_pair) {
String string;
for (int i = 0; i < p_entry.size(); i++) {
int pt_order = p_entry[i];
if (p_pair && ((i % 2) == 0)) {
string += itos(pt_order) + "-";
} else {
string += itos(pt_order) + ", ";
}
}
return string;
}
void VisualServerLightCuller::add_LUT(int p_plane_0, int p_plane_1, PointOrder p_pts[2]) {
uint32_t bit0 = 1 << p_plane_0;
uint32_t bit1 = 1 << p_plane_1;
// All entries of the LUT that have plane 0 set and plane 1 not set.
for (uint32_t n = 0; n < 64; n++) {
// If bit0 not set...
if (!(n & bit0))
continue;
// If bit1 set...
if (n & bit1)
continue;
// Meets criteria.
add_LUT_entry(n, p_pts);
}
}
void VisualServerLightCuller::add_LUT_entry(uint32_t p_entry_id, PointOrder p_pts[2]) {
DEV_ASSERT(p_entry_id < LUT_SIZE);
LocalVector<uint8_t> &entry = _calculated_LUT[p_entry_id];
entry.push_back(p_pts[0]);
entry.push_back(p_pts[1]);
}
void VisualServerLightCuller::compact_LUT_entry(uint32_t p_entry_id) {
DEV_ASSERT(p_entry_id < LUT_SIZE);
LocalVector<uint8_t> &entry = _calculated_LUT[p_entry_id];
int num_pairs = entry.size() / 2;
if (num_pairs == 0)
return;
LocalVector<uint8_t> temp;
String string;
string = "Compact LUT" + itos(p_entry_id) + ":\t";
string += debug_string_LUT_entry(entry, true);
print_line(string);
// Add first pair.
temp.push_back(entry[0]);
temp.push_back(entry[1]);
unsigned int BFpairs = 1;
string = debug_string_LUT_entry(temp) + " -> ";
print_line(string);
// Attempt to add a pair each time.
for (int done = 1; done < num_pairs; done++) {
string = "done " + itos(done) + ": ";
// Find a free pair.
for (int p = 1; p < num_pairs; p++) {
unsigned int bit = 1 << p;
// Is it done already?
if (BFpairs & bit)
continue;
// There must be at least 1 free pair.
// Attempt to add.
int a = entry[p * 2];
int b = entry[(p * 2) + 1];
string += "[" + itos(a) + "-" + itos(b) + "], ";
int found_a = temp.find(a);
int found_b = temp.find(b);
// Special case, if they are both already in the list, no need to add
// as this is a link from the tail to the head of the list.
if ((found_a != -1) && (found_b != -1)) {
string += "foundAB link " + itos(found_a) + ", " + itos(found_b) + " ";
BFpairs |= bit;
goto found;
}
// Find a.
if (found_a != -1) {
string += "foundA " + itos(found_a) + " ";
temp.insert(found_a + 1, b);
BFpairs |= bit;
goto found;
}
// Find b.
if (found_b != -1) {
string += "foundB " + itos(found_b) + " ";
temp.insert(found_b, a);
BFpairs |= bit;
goto found;
}
} // Check each pair for adding.
// If we got here before finding a link, the whole set of planes is INVALID
// e.g. far and near plane only, does not create continuous sillouhette of edges.
print_line("\tINVALID");
entry.clear();
return;
found:;
print_line(string);
string = "\ttemp now : " + debug_string_LUT_entry(temp);
print_line(string);
}
// temp should now be the sorted entry .. delete the old one and replace by temp.
entry.clear();
entry = temp;
}
void VisualServerLightCuller::get_neighbouring_planes(PlaneOrder p_plane, PlaneOrder r_neigh_planes[4]) const {
// Table of neighbouring planes to each.
static const PlaneOrder neigh_table[PLANE_TOTAL][4] = {
{ // LSM_FP_NEAR
PLANE_LEFT,
PLANE_RIGHT,
PLANE_TOP,
PLANE_BOTTOM },
{ // LSM_FP_FAR
PLANE_LEFT,
PLANE_RIGHT,
PLANE_TOP,
PLANE_BOTTOM },
{ // LSM_FP_LEFT
PLANE_TOP,
PLANE_BOTTOM,
PLANE_NEAR,
PLANE_FAR },
{ // LSM_FP_TOP
PLANE_LEFT,
PLANE_RIGHT,
PLANE_NEAR,
PLANE_FAR },
{ // LSM_FP_RIGHT
PLANE_TOP,
PLANE_BOTTOM,
PLANE_NEAR,
PLANE_FAR },
{ // LSM_FP_BOTTOM
PLANE_LEFT,
PLANE_RIGHT,
PLANE_NEAR,
PLANE_FAR },
};
for (int n = 0; n < 4; n++) {
r_neigh_planes[n] = neigh_table[p_plane][n];
}
}
// Given two planes, returns the two points shared by those planes. The points are always
// returned in counter-clockwise order, assuming the first input plane is facing towards
// the viewer.
// param p_plane_a The plane facing towards the viewer.
// param p_plane_b A plane neighboring p_plane_a.
// param r_points An array of exactly two elements to be filled with the indices of the points
// on return.
void VisualServerLightCuller::get_corners_of_planes(PlaneOrder p_plane_a, PlaneOrder p_plane_b, PointOrder r_points[2]) const {
static const PointOrder fp_table[PLANE_TOTAL][PLANE_TOTAL][2] = {
{
// LSM_FP_NEAR
{
// LSM_FP_NEAR
PT_NEAR_LEFT_TOP, PT_NEAR_RIGHT_TOP, // Invalid combination.
},
{
// LSM_FP_FAR
PT_FAR_RIGHT_TOP, PT_FAR_LEFT_TOP, // Invalid combination.
},
{
// LSM_FP_LEFT
PT_NEAR_LEFT_TOP,
PT_NEAR_LEFT_BOTTOM,
},
{
// LSM_FP_TOP
PT_NEAR_RIGHT_TOP,
PT_NEAR_LEFT_TOP,
},
{
// LSM_FP_RIGHT
PT_NEAR_RIGHT_BOTTOM,
PT_NEAR_RIGHT_TOP,
},
{
// LSM_FP_BOTTOM
PT_NEAR_LEFT_BOTTOM,
PT_NEAR_RIGHT_BOTTOM,
},
},
{
// LSM_FP_FAR
{
// LSM_FP_NEAR
PT_FAR_LEFT_TOP, PT_FAR_RIGHT_TOP, // Invalid combination.
},
{
// LSM_FP_FAR
PT_FAR_RIGHT_TOP, PT_FAR_LEFT_TOP, // Invalid combination.
},
{
// LSM_FP_LEFT
PT_FAR_LEFT_BOTTOM,
PT_FAR_LEFT_TOP,
},
{
// LSM_FP_TOP
PT_FAR_LEFT_TOP,
PT_FAR_RIGHT_TOP,
},
{
// LSM_FP_RIGHT
PT_FAR_RIGHT_TOP,
PT_FAR_RIGHT_BOTTOM,
},
{
// LSM_FP_BOTTOM
PT_FAR_RIGHT_BOTTOM,
PT_FAR_LEFT_BOTTOM,
},
},
{
// LSM_FP_LEFT
{
// LSM_FP_NEAR
PT_NEAR_LEFT_BOTTOM,
PT_NEAR_LEFT_TOP,
},
{
// LSM_FP_FAR
PT_FAR_LEFT_TOP,
PT_FAR_LEFT_BOTTOM,
},
{
// LSM_FP_LEFT
PT_FAR_LEFT_BOTTOM, PT_FAR_LEFT_BOTTOM, // Invalid combination.
},
{
// LSM_FP_TOP
PT_NEAR_LEFT_TOP,
PT_FAR_LEFT_TOP,
},
{
// LSM_FP_RIGHT
PT_FAR_LEFT_BOTTOM, PT_FAR_LEFT_BOTTOM, // Invalid combination.
},
{
// LSM_FP_BOTTOM
PT_FAR_LEFT_BOTTOM,
PT_NEAR_LEFT_BOTTOM,
},
},
{
// LSM_FP_TOP
{
// LSM_FP_NEAR
PT_NEAR_LEFT_TOP,
PT_NEAR_RIGHT_TOP,
},
{
// LSM_FP_FAR
PT_FAR_RIGHT_TOP,
PT_FAR_LEFT_TOP,
},
{
// LSM_FP_LEFT
PT_FAR_LEFT_TOP,
PT_NEAR_LEFT_TOP,
},
{
// LSM_FP_TOP
PT_NEAR_LEFT_TOP, PT_FAR_LEFT_TOP, // Invalid combination.
},
{
// LSM_FP_RIGHT
PT_NEAR_RIGHT_TOP,
PT_FAR_RIGHT_TOP,
},
{
// LSM_FP_BOTTOM
PT_FAR_LEFT_BOTTOM, PT_NEAR_LEFT_BOTTOM, // Invalid combination.
},
},
{
// LSM_FP_RIGHT
{
// LSM_FP_NEAR
PT_NEAR_RIGHT_TOP,
PT_NEAR_RIGHT_BOTTOM,
},
{
// LSM_FP_FAR
PT_FAR_RIGHT_BOTTOM,
PT_FAR_RIGHT_TOP,
},
{
// LSM_FP_LEFT
PT_FAR_RIGHT_BOTTOM, PT_FAR_RIGHT_BOTTOM, // Invalid combination.
},
{
// LSM_FP_TOP
PT_FAR_RIGHT_TOP,
PT_NEAR_RIGHT_TOP,
},
{
// LSM_FP_RIGHT
PT_FAR_RIGHT_BOTTOM, PT_FAR_RIGHT_BOTTOM, // Invalid combination.
},
{
// LSM_FP_BOTTOM
PT_NEAR_RIGHT_BOTTOM,
PT_FAR_RIGHT_BOTTOM,
},
},
// ==
// P_NEAR,
// P_FAR,
// P_LEFT,
// P_TOP,
// P_RIGHT,
// P_BOTTOM,
{
// LSM_FP_BOTTOM
{
// LSM_FP_NEAR
PT_NEAR_RIGHT_BOTTOM,
PT_NEAR_LEFT_BOTTOM,
},
{
// LSM_FP_FAR
PT_FAR_LEFT_BOTTOM,
PT_FAR_RIGHT_BOTTOM,
},
{
// LSM_FP_LEFT
PT_NEAR_LEFT_BOTTOM,
PT_FAR_LEFT_BOTTOM,
},
{
// LSM_FP_TOP
PT_NEAR_LEFT_BOTTOM, PT_FAR_LEFT_BOTTOM, // Invalid combination.
},
{
// LSM_FP_RIGHT
PT_FAR_RIGHT_BOTTOM,
PT_NEAR_RIGHT_BOTTOM,
},
{
// LSM_FP_BOTTOM
PT_FAR_LEFT_BOTTOM, PT_NEAR_LEFT_BOTTOM, // Invalid combination.
},
},
// ==
};
r_points[0] = fp_table[p_plane_a][p_plane_b][0];
r_points[1] = fp_table[p_plane_a][p_plane_b][1];
}
#endif
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