ardupilot/libraries/AP_Terrain/TerrainGCS.cpp

319 lines
9.3 KiB
C++

/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
handle vehicle <-> GCS communications for terrain library
*/
#include "AP_Terrain.h"
#include <AP_AHRS/AP_AHRS.h>
#include <AP_HAL/AP_HAL.h>
#include <AP_Common/AP_Common.h>
#include <AP_Math/AP_Math.h>
#include <GCS_MAVLink/GCS_MAVLink.h>
#include <GCS_MAVLink/GCS.h>
#if AP_TERRAIN_AVAILABLE
#include <assert.h>
#include <stdio.h>
extern const AP_HAL::HAL& hal;
/*
request any missing 4x4 grids from a block, given a grid_cache
*/
bool AP_Terrain::request_missing(mavlink_channel_t chan, struct grid_cache &gcache)
{
struct grid_block &grid = gcache.grid;
if (grid.spacing != grid_spacing) {
// an invalid grid
return false;
}
// see if we are waiting for disk read
if (gcache.state == GRID_CACHE_DISKWAIT) {
// don't request data from the GCS till we know it's not on disk
return false;
}
// see if it is fully populated
if ((grid.bitmap & bitmap_mask) == bitmap_mask) {
// it is fully populated, nothing to do
return false;
}
if (!HAVE_PAYLOAD_SPACE(chan, TERRAIN_REQUEST)) {
// not enough buffer space
return false;
}
/*
ask the GCS to send a set of 4x4 grids
*/
mavlink_msg_terrain_request_send(chan, grid.lat, grid.lon, grid_spacing, bitmap_mask & ~grid.bitmap);
last_request_time_ms[chan] = AP_HAL::millis();
return true;
}
/*
request any missing 4x4 grids from a block
*/
bool AP_Terrain::request_missing(mavlink_channel_t chan, const struct grid_info &info)
{
// find the grid
struct grid_cache &gcache = find_grid_cache(info);
return request_missing(chan, gcache);
}
/*
send any pending terrain request to the GCS
*/
void AP_Terrain::send_request(mavlink_channel_t chan)
{
if (!allocate()) {
// not enabled
return;
}
// see if we need to schedule some disk IO
schedule_disk_io();
Location loc;
if (!AP::ahrs().get_position(loc)) {
// we don't know where we are
return;
}
// always send a terrain report
send_terrain_report(chan, loc, true);
// did we request recently?
if (AP_HAL::millis() - last_request_time_ms[chan] < 2000) {
// too soon to request again
return;
}
// request any missing 4x4 blocks in the current grid
struct grid_info info;
calculate_grid_info(loc, info);
if (request_missing(chan, info)) {
return;
}
// also request a larger set of up to 9 grids
for (int8_t x=-1; x<=1; x++) {
for (int8_t y=-1; y<=1; y++) {
Location loc2 = loc;
loc2.offset(x*TERRAIN_GRID_BLOCK_SIZE_X*0.7f*grid_spacing,
y*TERRAIN_GRID_BLOCK_SIZE_Y*0.7f*grid_spacing);
struct grid_info info2;
calculate_grid_info(loc2, info2);
if (request_missing(chan, info2)) {
return;
}
}
}
// check cache blocks that may have been setup by a TERRAIN_CHECK
for (uint16_t i=0; i<cache_size; i++) {
if (cache[i].state >= GRID_CACHE_VALID) {
if (request_missing(chan, cache[i])) {
return;
}
}
}
// request the current loc last to ensure it has highest last
// access time
if (request_missing(chan, info)) {
return;
}
}
/*
count bits in a uint64_t
*/
uint8_t AP_Terrain::bitcount64(uint64_t b) const
{
return __builtin_popcount((unsigned)(b&0xFFFFFFFF)) + __builtin_popcount((unsigned)(b>>32));
}
/*
get some statistics for TERRAIN_REPORT
*/
void AP_Terrain::get_statistics(uint16_t &pending, uint16_t &loaded) const
{
pending = 0;
loaded = 0;
for (uint16_t i=0; i<cache_size; i++) {
if (cache[i].grid.spacing != grid_spacing) {
continue;
}
if (cache[i].state == GRID_CACHE_INVALID) {
continue;
}
uint8_t maskbits = TERRAIN_GRID_BLOCK_MUL_X*TERRAIN_GRID_BLOCK_MUL_Y;
if (cache[i].state == GRID_CACHE_DISKWAIT) {
pending += maskbits;
continue;
}
if (cache[i].state == GRID_CACHE_DIRTY) {
// count dirty grids as a pending, so we know where there
// are disk writes pending
pending++;
}
uint8_t bitcount = bitcount64(cache[i].grid.bitmap);
pending += maskbits - bitcount;
loaded += bitcount;
}
}
/*
handle terrain messages from GCS
*/
void AP_Terrain::handle_data(mavlink_channel_t chan, const mavlink_message_t &msg)
{
if (msg.msgid == MAVLINK_MSG_ID_TERRAIN_DATA) {
handle_terrain_data(msg);
} else if (msg.msgid == MAVLINK_MSG_ID_TERRAIN_CHECK) {
handle_terrain_check(chan, msg);
}
}
/*
send a TERRAIN_REPORT for a location
*/
void AP_Terrain::send_terrain_report(mavlink_channel_t chan, const Location &loc, bool extrapolate)
{
float terrain_height = 0;
float home_terrain_height = 0;
uint16_t spacing = 0;
Location current_loc;
const AP_AHRS &ahrs = AP::ahrs();
if (ahrs.get_position(current_loc) &&
height_amsl(ahrs.get_home(), home_terrain_height, false) &&
height_amsl(loc, terrain_height, false)) {
// non-zero spacing indicates we have data
spacing = grid_spacing;
} else if (extrapolate && have_current_loc_height) {
// show the extrapolated height, so logs show what height is
// being used for navigation
terrain_height = last_current_loc_height;
}
uint16_t pending, loaded;
get_statistics(pending, loaded);
float current_height;
if (spacing == 0 && !(extrapolate && have_current_loc_height)) {
current_height = 0;
} else {
if (current_loc.relative_alt) {
current_height = current_loc.alt*0.01f;
} else {
current_height = (current_loc.alt - ahrs.get_home().alt)*0.01f;
}
}
current_height += home_terrain_height - terrain_height;
if (HAVE_PAYLOAD_SPACE(chan, TERRAIN_REPORT)) {
mavlink_msg_terrain_report_send(chan, loc.lat, loc.lng, spacing,
terrain_height, current_height,
pending, loaded);
}
}
/*
handle TERRAIN_CHECK messages from GCS
*/
void AP_Terrain::handle_terrain_check(mavlink_channel_t chan, const mavlink_message_t &msg)
{
mavlink_terrain_check_t packet;
mavlink_msg_terrain_check_decode(&msg, &packet);
Location loc;
loc.lat = packet.lat;
loc.lng = packet.lon;
send_terrain_report(chan, loc, false);
}
/*
handle TERRAIN_DATA messages from GCS
*/
void AP_Terrain::handle_terrain_data(const mavlink_message_t &msg)
{
mavlink_terrain_data_t packet;
mavlink_msg_terrain_data_decode(&msg, &packet);
uint16_t i;
for (i=0; i<cache_size; i++) {
if (cache[i].grid.lat == packet.lat &&
cache[i].grid.lon == packet.lon &&
cache[i].grid.spacing == packet.grid_spacing &&
grid_spacing == packet.grid_spacing &&
packet.gridbit < 56) {
break;
}
}
if (i == cache_size) {
// we don't have that grid, ignore data
return;
}
struct grid_cache &gcache = cache[i];
struct grid_block &grid = gcache.grid;
uint8_t idx_x = (packet.gridbit / TERRAIN_GRID_BLOCK_MUL_Y) * TERRAIN_GRID_MAVLINK_SIZE;
uint8_t idx_y = (packet.gridbit % TERRAIN_GRID_BLOCK_MUL_Y) * TERRAIN_GRID_MAVLINK_SIZE;
ASSERT_RANGE(idx_x,0,(TERRAIN_GRID_BLOCK_MUL_X-1)*TERRAIN_GRID_MAVLINK_SIZE);
ASSERT_RANGE(idx_y,0,(TERRAIN_GRID_BLOCK_MUL_Y-1)*TERRAIN_GRID_MAVLINK_SIZE);
for (uint8_t x=0; x<TERRAIN_GRID_MAVLINK_SIZE; x++) {
for (uint8_t y=0; y<TERRAIN_GRID_MAVLINK_SIZE; y++) {
grid.height[idx_x+x][idx_y+y] = packet.data[x*TERRAIN_GRID_MAVLINK_SIZE+y];
}
}
gcache.grid.bitmap |= ((uint64_t)1) << packet.gridbit;
// mark dirty for disk IO
gcache.state = GRID_CACHE_DIRTY;
#if TERRAIN_DEBUG
hal.console->printf("Filled bit %u idx_x=%u idx_y=%u\n",
(unsigned)packet.gridbit, (unsigned)idx_x, (unsigned)idx_y);
if (gcache.grid.bitmap == bitmap_mask) {
hal.console->printf("--lat=%12.7f --lon=%12.7f %u\n",
grid.lat*1.0e-7f,
grid.lon*1.0e-7f,
grid.height[0][0]);
Location loc2;
loc2.lat = grid.lat;
loc2.lng = grid.lon;
loc2.offset(28*grid_spacing, 32*grid_spacing);
hal.console->printf("--lat=%12.7f --lon=%12.7f %u\n",
loc2.lat*1.0e-7f,
loc2.lng*1.0e-7f,
grid.height[27][31]);
}
#endif
// see if we need to schedule some disk IO
update();
}
#endif // AP_TERRAIN_AVAILABLE