115f4dce55
Add framework for supporting geometrical occluders within rooms, and add support for sphere occluders. Includes gizmos for editing. They also work outside the portal system.
568 lines
20 KiB
C++
568 lines
20 KiB
C++
/*************************************************************************/
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/* portal_tracer.cpp */
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/*************************************************************************/
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/* This file is part of: */
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/* GODOT ENGINE */
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/* https://godotengine.org */
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/*************************************************************************/
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/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
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/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
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/* */
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/* Permission is hereby granted, free of charge, to any person obtaining */
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/* a copy of this software and associated documentation files (the */
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/* "Software"), to deal in the Software without restriction, including */
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/* without limitation the rights to use, copy, modify, merge, publish, */
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/* distribute, sublicense, and/or sell copies of the Software, and to */
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/* permit persons to whom the Software is furnished to do so, subject to */
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/* the following conditions: */
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/* */
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/* The above copyright notice and this permission notice shall be */
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/* included in all copies or substantial portions of the Software. */
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/* */
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/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
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/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
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/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
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/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
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/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
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/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
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/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
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/*************************************************************************/
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#include "portal_tracer.h"
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#include "portal_renderer.h"
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#include "servers/visual/visual_server_globals.h"
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#include "servers/visual/visual_server_scene.h"
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PortalTracer::PlanesPool::PlanesPool() {
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reset();
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// preallocate the vectors to a reasonable size
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for (int n = 0; n < POOL_MAX; n++) {
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_planes[n].resize(32);
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}
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}
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void PortalTracer::PlanesPool::reset() {
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for (int n = 0; n < POOL_MAX; n++) {
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_freelist[n] = POOL_MAX - n - 1;
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}
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_num_free = POOL_MAX;
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}
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unsigned int PortalTracer::PlanesPool::request() {
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if (!_num_free) {
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return -1;
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}
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_num_free--;
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return _freelist[_num_free];
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}
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void PortalTracer::PlanesPool::free(unsigned int ui) {
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DEV_ASSERT(ui < POOL_MAX);
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DEV_ASSERT(_num_free < POOL_MAX);
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_freelist[_num_free] = ui;
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_num_free++;
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}
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void PortalTracer::trace_debug_sprawl(PortalRenderer &p_portal_renderer, const Vector3 &p_pos, int p_start_room_id, TraceResult &r_result) {
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_portal_renderer = &p_portal_renderer;
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_trace_start_point = p_pos;
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_result = &r_result;
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// all the statics should be not hit to start with
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_result->clear();
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// new test, new tick, to prevent hitting objects more than once
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// on a test.
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_tick++;
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// if the camera is not in a room do nothing
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if (p_start_room_id == -1) {
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return;
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}
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trace_debug_sprawl_recursive(0, p_start_room_id);
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}
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void PortalTracer::trace(PortalRenderer &p_portal_renderer, const Vector3 &p_pos, const LocalVector<Plane> &p_planes, int p_start_room_id, TraceResult &r_result) {
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// store local versions to prevent passing around recursive functions
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_portal_renderer = &p_portal_renderer;
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_trace_start_point = p_pos;
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_result = &r_result;
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// The near and far clipping planes needs special treatment. The problem is, if it is
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// say a metre from the camera, it will clip out a portal immediately in front of the camera.
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// as a result we want to use the near clipping plane for objects, but construct a fake
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// near plane at exactly the position of the camera, to clip out portals that are behind us.
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_near_and_far_planes[0] = p_planes[0];
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_near_and_far_planes[1] = p_planes[1];
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// all the statics should be not hit to start with
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_result->clear();
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// new test, new tick, to prevent hitting objects more than once
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// on a test.
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_tick++;
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// if the camera is not in a room do nothing
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// (this will return no hits, but is unlikely because the find_rooms lookup will return the nearest
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// room even if not inside)
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if (p_start_room_id == -1) {
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return;
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}
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// start off the trace with the planes from the camera
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LocalVector<Plane> cam_planes;
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cam_planes = p_planes;
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if (p_portal_renderer.get_cull_using_pvs()) {
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trace_pvs(p_start_room_id, cam_planes);
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} else {
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// alternative : instead of copying straight, we create the first (near) clipping
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// plane manually, at 0 distance from the camera. This ensures that portals will not be
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// missed, while still culling portals and objects behind us. If we use the actual near clipping plane
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// then a portal in front of the camera may not be seen through, giving glitches
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cam_planes[0] = Plane(p_pos, cam_planes[0].normal);
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TraceParams params;
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params.use_pvs = p_portal_renderer.get_pvs().is_loaded();
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// create bitfield
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if (params.use_pvs) {
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const PVS &pvs = _portal_renderer->get_pvs();
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if (!pvs.get_pvs_size()) {
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params.use_pvs = false;
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} else {
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// decompress a simple to read roomlist bitfield (could use bits maybe but bytes ok for now)
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params.decompressed_room_pvs = nullptr;
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params.decompressed_room_pvs = (uint8_t *)alloca(sizeof(uint8_t) * pvs.get_pvs_size());
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memset(params.decompressed_room_pvs, 0, sizeof(uint8_t) * pvs.get_pvs_size());
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const VSRoom &source_room = _portal_renderer->get_room(p_start_room_id);
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for (int n = 0; n < source_room._pvs_size; n++) {
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int room_id = pvs.get_pvs_room_id(source_room._pvs_first + n);
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params.decompressed_room_pvs[room_id] = 255;
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}
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}
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}
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trace_recursive(params, 0, p_start_room_id, cam_planes);
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}
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}
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void PortalTracer::cull_roamers(const VSRoom &p_room, const LocalVector<Plane> &p_planes) {
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int num_roamers = p_room._roamer_pool_ids.size();
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for (int n = 0; n < num_roamers; n++) {
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uint32_t pool_id = p_room._roamer_pool_ids[n];
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PortalRenderer::Moving &moving = _portal_renderer->get_pool_moving(pool_id);
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// done already?
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if (moving.last_tick_hit == _tick) {
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continue;
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}
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if (test_cull_inside(moving.exact_aabb, p_planes)) {
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if (!_occlusion_culler.cull_aabb(moving.exact_aabb)) {
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// mark as done (and on visible list)
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moving.last_tick_hit = _tick;
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_result->visible_roamer_pool_ids.push_back(pool_id);
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}
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}
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}
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}
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void PortalTracer::cull_statics_debug_sprawl(const VSRoom &p_room) {
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int num_statics = p_room._static_ids.size();
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for (int n = 0; n < num_statics; n++) {
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uint32_t static_id = p_room._static_ids[n];
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// VSStatic &stat = _portal_renderer->get_static(static_id);
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// deal with dynamic stats
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// if (stat.dynamic) {
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// VSG::scene->_instance_get_transformed_aabb(stat.instance, stat.aabb);
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// }
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// set the visible bit if not set
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if (!_result->bf_visible_statics.check_and_set(static_id)) {
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_result->visible_static_ids.push_back(static_id);
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}
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}
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}
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void PortalTracer::cull_statics(const VSRoom &p_room, const LocalVector<Plane> &p_planes) {
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int num_statics = p_room._static_ids.size();
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for (int n = 0; n < num_statics; n++) {
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uint32_t static_id = p_room._static_ids[n];
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VSStatic &stat = _portal_renderer->get_static(static_id);
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// deal with dynamic stats
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if (stat.dynamic) {
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VSG::scene->_instance_get_transformed_aabb(stat.instance, stat.aabb);
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}
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// estimate the radius .. for now
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const AABB &bb = stat.aabb;
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// print("\t\t\tculling object " + pObj->get_name());
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if (test_cull_inside(bb, p_planes)) {
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if (_occlusion_culler.cull_aabb(bb)) {
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continue;
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}
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// bypass the bitfield for now and just show / hide
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//stat.show(bShow);
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// set the visible bit if not set
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if (_result->bf_visible_statics.check_and_set(static_id)) {
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// if wasn't previously set, add to the visible list
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_result->visible_static_ids.push_back(static_id);
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}
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}
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} // for n through statics
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}
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int PortalTracer::trace_globals(const LocalVector<Plane> &p_planes, VSInstance **p_result_array, int first_result, int p_result_max, uint32_t p_mask, bool p_override_camera) {
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uint32_t num_globals = _portal_renderer->get_num_moving_globals();
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int current_result = first_result;
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if (!p_override_camera) {
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for (uint32_t n = 0; n < num_globals; n++) {
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const PortalRenderer::Moving &moving = _portal_renderer->get_moving_global(n);
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#ifdef PORTAL_RENDERER_STORE_MOVING_RIDS
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// debug check the instance is valid
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void *vss_instance = VSG::scene->_instance_get_from_rid(moving.instance_rid);
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if (vss_instance) {
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#endif
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if (test_cull_inside(moving.exact_aabb, p_planes, false)) {
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if (VSG::scene->_instance_cull_check(moving.instance, p_mask)) {
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p_result_array[current_result++] = moving.instance;
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// full up?
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if (current_result >= p_result_max) {
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return current_result;
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}
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}
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}
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#ifdef PORTAL_RENDERER_STORE_MOVING_RIDS
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} else {
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WARN_PRINT("vss instance is null " + PortalRenderer::_addr_to_string(moving.instance));
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}
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#endif
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}
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} // if not override camera
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else {
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// If we are overriding the camera there is a potential problem in the editor:
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// gizmos BEHIND the override camera will not be drawn.
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// As this should be editor only and performance is not critical, we will just disable
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// frustum culling for global objects when the camera is overriden.
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for (uint32_t n = 0; n < num_globals; n++) {
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const PortalRenderer::Moving &moving = _portal_renderer->get_moving_global(n);
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if (VSG::scene->_instance_cull_check(moving.instance, p_mask)) {
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p_result_array[current_result++] = moving.instance;
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// full up?
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if (current_result >= p_result_max) {
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return current_result;
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}
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}
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}
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} // if override camera
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return current_result;
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}
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void PortalTracer::trace_debug_sprawl_recursive(int p_depth, int p_room_id) {
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if (p_depth > 1) {
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return;
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}
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// prevent too much depth
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ERR_FAIL_COND_MSG(p_depth > 8, "Portal Depth Limit reached");
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// get the room
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const VSRoom &room = _portal_renderer->get_room(p_room_id);
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int num_portals = room._portal_ids.size();
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for (int p = 0; p < num_portals; p++) {
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const VSPortal &portal = _portal_renderer->get_portal(room._portal_ids[p]);
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if (!portal._active) {
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continue;
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}
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cull_statics_debug_sprawl(room);
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// everything depends on whether the portal is incoming or outgoing.
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int outgoing = 1;
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int room_a_id = portal._linkedroom_ID[0];
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if (room_a_id != p_room_id) {
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outgoing = 0;
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DEV_ASSERT(portal._linkedroom_ID[1] == p_room_id);
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}
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// trace through this portal to the next room
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int linked_room_id = portal._linkedroom_ID[outgoing];
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if (linked_room_id != -1) {
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trace_debug_sprawl_recursive(p_depth + 1, linked_room_id);
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} // if a linked room exists
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} // for p through portals
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}
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void PortalTracer::trace_pvs(int p_source_room_id, const LocalVector<Plane> &p_planes) {
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const PVS &pvs = _portal_renderer->get_pvs();
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const VSRoom &source_room = _portal_renderer->get_room(p_source_room_id);
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for (int r = 0; r < source_room._pvs_size; r++) {
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int room_id = pvs.get_pvs_room_id(source_room._pvs_first + r);
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// get the room
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const VSRoom &room = _portal_renderer->get_room(room_id);
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cull_statics(room, p_planes);
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cull_roamers(room, p_planes);
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}
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}
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void PortalTracer::trace_recursive(const TraceParams &p_params, int p_depth, int p_room_id, const LocalVector<Plane> &p_planes, int p_from_external_room_id) {
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// prevent too much depth
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if (p_depth > _depth_limit) {
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WARN_PRINT_ONCE("Portal Depth Limit reached (seeing through too many portals)");
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return;
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}
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// get the room
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const VSRoom &room = _portal_renderer->get_room(p_room_id);
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// set up the occlusion culler as a one off
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_occlusion_culler.prepare(*_portal_renderer, room, _trace_start_point, p_planes, &_near_and_far_planes[0]);
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cull_statics(room, p_planes);
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cull_roamers(room, p_planes);
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int num_portals = room._portal_ids.size();
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for (int p = 0; p < num_portals; p++) {
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const VSPortal &portal = _portal_renderer->get_portal(room._portal_ids[p]);
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// portals can be switched on and off at runtime, like opening and closing a door
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if (!portal._active) {
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continue;
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}
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// everything depends on whether the portal is incoming or outgoing.
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// if incoming we reverse the logic.
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int outgoing = 1;
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int room_a_id = portal._linkedroom_ID[0];
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if (room_a_id != p_room_id) {
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outgoing = 0;
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DEV_ASSERT(portal._linkedroom_ID[1] == p_room_id);
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}
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// trace through this portal to the next room
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int linked_room_id = portal._linkedroom_ID[outgoing];
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// cull by PVS
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if (p_params.use_pvs && (!p_params.decompressed_room_pvs[linked_room_id])) {
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continue;
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}
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// cull by portal angle to camera.
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// much better way of culling portals by direction to camera...
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// instead of using dot product with a varying view direction, we simply find which side of the portal
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// plane the camera is on! If it is behind, the portal can be seen through, if in front, it can't
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real_t dist_cam = portal._plane.distance_to(_trace_start_point);
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if (!outgoing) {
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dist_cam = -dist_cam;
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}
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if (dist_cam >= 0.0) {
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continue;
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}
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// is it culled by the planes?
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VSPortal::ClipResult overall_res = VSPortal::ClipResult::CLIP_INSIDE;
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// while clipping to the planes we maintain a list of partial planes, so we can add them to the
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// recursive next iteration of planes to check
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static LocalVector<int> partial_planes;
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partial_planes.clear();
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// for portals, we want to ignore the near clipping plane, as we might be right on the edge of a doorway
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// and still want to look through the portal.
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// so earlier we have set it that the first plane (ASSUMING that plane zero is the near clipping plane)
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// starts from the camera position, and NOT the actual near clipping plane.
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// if we need quite a distant near plane, we may need a different strategy.
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for (uint32_t l = 0; l < p_planes.size(); l++) {
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VSPortal::ClipResult res = portal.clip_with_plane(p_planes[l]);
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switch (res) {
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case VSPortal::ClipResult::CLIP_OUTSIDE: {
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overall_res = res;
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} break;
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case VSPortal::ClipResult::CLIP_PARTIAL: {
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// if the portal intersects one of the planes, we should take this plane into account
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// in the next call of this recursive trace, because it can be used to cull out more objects
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overall_res = res;
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partial_planes.push_back(l);
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} break;
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default: // suppress warning
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break;
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}
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// if the portal was totally outside the 'frustum' then we can ignore it
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if (overall_res == VSPortal::ClipResult::CLIP_OUTSIDE)
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break;
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}
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// this portal is culled
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if (overall_res == VSPortal::ClipResult::CLIP_OUTSIDE) {
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continue;
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}
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// Don't allow portals from internal to external room to be followed
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// if the external room has already been processed in this trace stack. This prevents
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// unneeded processing, and also prevents recursive feedback where you
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// see into internal room -> external room and back into the same internal room
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// via the same portal.
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if (portal._internal && (linked_room_id != -1)) {
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if (outgoing) {
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if (linked_room_id == p_from_external_room_id) {
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continue;
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}
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} else {
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// We are entering an internal portal from an external room.
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// set the external room id, so we can recognise this when we are
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// later exiting the internal rooms.
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// Note that as we can only store 1 previous external room, this system
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// won't work completely correctly when you have 2 levels of internal room
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// and you can see from roomgroup a -> b -> c. However this should just result
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// in a little slower culling for that particular view, and hopefully will not break
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// with recursive loop looking through the same portal multiple times. (don't think this
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// is possible in this scenario).
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p_from_external_room_id = p_room_id;
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}
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}
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// occlusion culling of portals
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if (_occlusion_culler.cull_sphere(portal._pt_center, portal._bounding_sphere_radius)) {
|
|
continue;
|
|
}
|
|
|
|
// hopefully the portal actually leads somewhere...
|
|
if (linked_room_id != -1) {
|
|
// we need some new planes
|
|
unsigned int pool_mem = _planes_pool.request();
|
|
|
|
// if the planes pool is not empty, we got some planes, and can recurse
|
|
if (pool_mem != (unsigned int)-1) {
|
|
// get a new vector of planes from the pool
|
|
LocalVector<Plane> &new_planes = _planes_pool.get(pool_mem);
|
|
|
|
// makes sure there are none left over (as the pool may not clear them)
|
|
new_planes.clear();
|
|
|
|
// if portal is totally inside the planes, don't copy the old planes ..
|
|
// i.e. we can now cull using the portal and forget about the rest of the frustum (yay)
|
|
// note that this loses the far clipping plane .. but that shouldn't be important usually?
|
|
// (maybe we might need to account for this in future .. look for issues)
|
|
if (overall_res != VSPortal::ClipResult::CLIP_INSIDE) {
|
|
// if it WASNT totally inside the existing frustum, we also need to add any existing planes
|
|
// that cut the portal.
|
|
for (uint32_t n = 0; n < partial_planes.size(); n++) {
|
|
new_planes.push_back(p_planes[partial_planes[n]]);
|
|
}
|
|
}
|
|
|
|
// we will always add the portals planes. This could probably be optimized, as some
|
|
// portal planes may be culled out by partial planes... NYI
|
|
portal.add_planes(_trace_start_point, new_planes, outgoing != 0);
|
|
|
|
// always add the far plane. It is likely the portal is inside the far plane,
|
|
// but it is still needed in future for culling portals and objects.
|
|
// note that there is a small possibility of far plane being added twice here
|
|
// in some situations, but I don't think it should be a problem.
|
|
// The fake near plane BTW is almost never added (otherwise it would prematurely
|
|
// break traversal through the portals), so near clipping must be done
|
|
// explicitly on objects.
|
|
new_planes.push_back(_near_and_far_planes[1]);
|
|
|
|
// go and do the whole lot again in the next room
|
|
trace_recursive(p_params, p_depth + 1, linked_room_id, new_planes, p_from_external_room_id);
|
|
|
|
// no longer need these planes, return them to the pool
|
|
_planes_pool.free(pool_mem);
|
|
|
|
} // pool mem allocated
|
|
else {
|
|
// planes pool is empty!
|
|
// This will happen if the view goes through shedloads of portals
|
|
// The solution is either to increase the plane pool size, or not build levels
|
|
// with views through multiple portals. Looking through multiple portals is likely to be
|
|
// slow anyway because of the number of planes to test.
|
|
WARN_PRINT_ONCE("planes pool is empty");
|
|
// note we also have a depth check at the top of this function. Which will probably get hit
|
|
// before the pool gets empty.
|
|
}
|
|
|
|
} // if a linked room exists
|
|
} // for p through portals
|
|
}
|
|
|
|
int PortalTracer::occlusion_cull(PortalRenderer &p_portal_renderer, const Vector3 &p_point, const Vector<Plane> &p_convex, VSInstance **p_result_array, int p_num_results) {
|
|
// silly conversion of vector to local vector
|
|
// can this be avoided? NYI
|
|
// pretty cheap anyway as it will just copy 6 planes, max a few times per frame...
|
|
static LocalVector<Plane> local_planes;
|
|
if ((int)local_planes.size() != p_convex.size()) {
|
|
local_planes.resize(p_convex.size());
|
|
}
|
|
for (int n = 0; n < p_convex.size(); n++) {
|
|
local_planes[n] = p_convex[n];
|
|
}
|
|
|
|
_occlusion_culler.prepare_generic(p_portal_renderer, p_portal_renderer.get_occluders_active_list(), p_point, local_planes, nullptr);
|
|
|
|
// cull each instance
|
|
int count = p_num_results;
|
|
AABB bb;
|
|
|
|
for (int n = 0; n < count; n++) {
|
|
VSInstance *instance = p_result_array[n];
|
|
|
|
// this will return false for GLOBAL instances, so we don't occlusion cull gizmos
|
|
if (VSG::scene->_instance_get_transformed_aabb_for_occlusion(instance, bb)) {
|
|
if (_occlusion_culler.cull_aabb(bb)) {
|
|
// remove from list with unordered swap from the end of list
|
|
p_result_array[n] = p_result_array[count - 1];
|
|
count--;
|
|
n--; // repeat this element, as it will have changed
|
|
}
|
|
}
|
|
}
|
|
|
|
return count;
|
|
}
|