/* This function not only seeks to the specified point, but also reads
* the point into the buffer if necessary. The get_singlepoint function
* then only transfers the data. */
LOCAL void
read_synamps_seek_point(transform_info_ptr tinfo, long point) {
struct read_synamps_storage *local_arg=(struct read_synamps_storage *)tinfo->methods->local_storage;
switch(local_arg->SubType) {
case NST_CONT0:
case NST_DCMES:
case NST_CONTINUOUS:
case NST_SYNAMPS: {
/*{{{ */
const int points_per_buf=local_arg->EEG.ChannelOffset/local_arg->bytes_per_sample; /* Note a value of 1 is fixed in read_synamps_init */
long const buffer_boundary=(point/points_per_buf)*points_per_buf;
long const new_last_point_in_buffer=buffer_boundary+points_per_buf-1;
/* This format is neither points fastest nor channels fastest, but
* points fastest in blocks. No idea why they didn't do channels fastest,
* it would have rendered the whole file in one order, no matter what buffer
* size is used internally in programs. This way we MUST use the given buffers. */
if (new_last_point_in_buffer!=local_arg->last_point_in_buffer) {
fseek(local_arg->SCAN,point2offset(tinfo,buffer_boundary),SEEK_SET);
if (fread(local_arg->buffer,1,local_arg->BufferCount,local_arg->SCAN)!=local_arg->BufferCount) {
ERREXIT(tinfo->emethods, "read_synamps_seek_point: Error reading data\n");
}
local_arg->first_point_in_buffer=buffer_boundary;
local_arg->last_point_in_buffer=new_last_point_in_buffer;
/*{{{ Swap byte order if necessary*/
# ifndef LITTLE_ENDIAN
{uint16_t *pdata=(uint16_t *)local_arg->buffer, *p_end=(uint16_t *)((char *)local_arg->buffer+local_arg->BufferCount);
while (pdata<p_end) Intel_int16(pdata++);
}
# endif
/*}}} */
}
/*}}} */
}
break;
default:
ERREXIT1(tinfo->emethods, "read_synamps_seek_point: Format `%s' is not yet supported\n", MSGPARM(neuroscan_subtype_names[local_arg->SubType]));
break;
}
local_arg->current_point=point;
}
} else {
resp=(-intrig->code)&0xf;
if (resp==0) {
keyboard=(-intrig->code)>>4;
if (keyboard==0) {
TRACEMS1(tinfo->emethods, 1, "write_synamps_exit: Can't decipher event code %d\n", MSGPARM(intrig->code));
} else {
keyboard--;
}
}
}
}
event.StimType=type; event.KeyBoard=keyboard;
Event_KeyPad_set(event, resp);
Event_Accept_set(event, acc);
event.Offset=point2offset(tinfo, intrig->position);
# ifndef LITTLE_ENDIAN
change_byteorder((char *)&event, sm_EVENT1);
# endif
write_struct((char *)&event, sm_EVENT1, local_arg->SCAN);
}
if (local_arg->triggers.buffer_start!=NULL) {
clear_triggers(&local_arg->triggers);
growing_buf_free(&local_arg->triggers);
}
/* Write the end event */
event.StimType=0; event.KeyBoard=0;
Event_KeyPad_set(event, 0);
Event_Accept_set(event, NAV_STARTSTOP);
