/**
* @brief Writes a delta update of an entity_state_t list to the message.
*/
static void Sv_WriteEntities(sv_frame_t *from, sv_frame_t *to, mem_buf_t *msg) {
entity_state_t *old_state = NULL, *new_state = NULL;
uint32_t old_index, new_index;
uint16_t old_num, new_num;
uint16_t from_num_entities;
if (!from) {
from_num_entities = 0;
} else {
from_num_entities = from->num_entities;
}
new_index = 0;
old_index = 0;
while (new_index < to->num_entities || old_index < from_num_entities) {
if (new_index >= to->num_entities) {
new_num = 0xffff;
} else {
new_state = &svs.entity_states[(to->entity_state + new_index) % svs.num_entity_states];
new_num = new_state->number;
}
if (old_index >= from_num_entities) {
old_num = 0xffff;
} else {
old_state
= &svs.entity_states[(from->entity_state + old_index) % svs.num_entity_states];
old_num = old_state->number;
}
if (new_num == old_num) { // delta update from old position
Net_WriteDeltaEntity(msg, old_state, new_state, false);
old_index++;
new_index++;
continue;
}
if (new_num < old_num) { // this is a new entity, send it from the baseline
Net_WriteDeltaEntity(msg, &sv.baselines[new_num], new_state, true);
new_index++;
continue;
}
if (new_num > old_num) { // the old entity isn't present in the new message
const int16_t bits = U_REMOVE;
Net_WriteShort(msg, old_num);
Net_WriteShort(msg, bits);
old_index++;
continue;
}
}
Net_WriteShort(msg, 0); // end of entities
}
/**
* @brief Writes server_data, config_strings, and baselines once a non-delta
* compressed frame arrives from the server.
*/
static void Cl_WriteDemoHeader(void) {
static entity_state_t null_state;
mem_buf_t msg;
byte buffer[MAX_MSG_SIZE];
// write out messages to hold the startup information
Mem_InitBuffer(&msg, buffer, sizeof(buffer));
// write the server data
Net_WriteByte(&msg, SV_CMD_SERVER_DATA);
Net_WriteShort(&msg, PROTOCOL_MAJOR);
Net_WriteShort(&msg, cls.cgame->protocol);
Net_WriteByte(&msg, 1); // demo_server byte
Net_WriteString(&msg, Cvar_GetString("game"));
Net_WriteShort(&msg, cl.client_num);
Net_WriteString(&msg, cl.config_strings[CS_NAME]);
// and config_strings
for (int32_t i = 0; i < MAX_CONFIG_STRINGS; i++) {
if (*cl.config_strings[i] != '\0') {
if (msg.size + strlen(cl.config_strings[i]) + 32 > msg.max_size) { // write it out
const int32_t len = LittleLong((int32_t) msg.size);
Fs_Write(cls.demo_file, &len, sizeof(len), 1);
Fs_Write(cls.demo_file, msg.data, msg.size, 1);
msg.size = 0;
}
Net_WriteByte(&msg, SV_CMD_CONFIG_STRING);
Net_WriteShort(&msg, i);
Net_WriteString(&msg, cl.config_strings[i]);
}
}
// and baselines
for (size_t i = 0; i < lengthof(cl.entities); i++) {
entity_state_t *ent = &cl.entities[i].baseline;
if (!ent->number) {
continue;
}
if (msg.size + 64 > msg.max_size) { // write it out
const int32_t len = LittleLong((int32_t) msg.size);
Fs_Write(cls.demo_file, &len, sizeof(len), 1);
Fs_Write(cls.demo_file, msg.data, msg.size, 1);
msg.size = 0;
}
Net_WriteByte(&msg, SV_CMD_BASELINE);
Net_WriteDeltaEntity(&msg, &null_state, &cl.entities[i].baseline, true);
}
Net_WriteByte(&msg, SV_CMD_CBUF_TEXT);
Net_WriteString(&msg, "precache 0\n");
// write it to the demo file
const int32_t len = LittleLong((int32_t) msg.size);
Fs_Write(cls.demo_file, &len, sizeof(len), 1);
Fs_Write(cls.demo_file, msg.data, msg.size, 1);
Com_Debug(DEBUG_CLIENT, "Demo started\n");
// the rest of the demo file will be individual frames
}
