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DISCRETE_CRFILTER, DISCRETE_RCFILTER

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- optimized my recent changes.  Not worth mentioning.
This commit is contained in:
Derrick Renaud 2009-10-06 23:24:17 +00:00
parent 37443dbc67
commit 0d1660e579
1 changed files with 17 additions and 10 deletions
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11
src/emu/sound/disc_flt.c
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@ -99,6 +99,7 @@ struct dst_rcfilter_context
double vCap; double vCap;
double rc; double rc;
double exponent; double exponent;
UINT8 has_rc_nodes;
}; };
struct dst_rcfilter_sw_context struct dst_rcfilter_sw_context
@ -147,13 +148,15 @@ static DISCRETE_STEP(dst_crfilter)
{ {
struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context; struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context;
if (context->has_rc_nodes)
{
double rc = DST_CRFILTER__R * DST_CRFILTER__C; double rc = DST_CRFILTER__R * DST_CRFILTER__C;
if (rc != context->rc) if (rc != context->rc)
{ {
context->rc = rc; context->rc = rc;
context->exponent = RC_CHARGE_EXP(rc); context->exponent = RC_CHARGE_EXP(rc);
} }
}
node->output[0] = DST_CRFILTER__IN - context->vCap; node->output[0] = DST_CRFILTER__IN - context->vCap;
//context->vCap += ((DST_CRFILTER__IN - context->vRef) - context->vCap) * context->exponent; //context->vCap += ((DST_CRFILTER__IN - context->vRef) - context->vCap) * context->exponent;
@ -164,6 +167,7 @@ static DISCRETE_RESET(dst_crfilter)
{ {
struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context; struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context;
context->has_rc_nodes = node->input_is_node & 0x6;
context->rc = DST_CRFILTER__R * DST_CRFILTER__C; context->rc = DST_CRFILTER__R * DST_CRFILTER__C;
context->exponent = RC_CHARGE_EXP(context->rc); context->exponent = RC_CHARGE_EXP(context->rc);
context->vCap = 0; context->vCap = 0;
@ -1029,13 +1033,15 @@ static DISCRETE_STEP(dst_rcfilter)
{ {
struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context; struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context;
if (context->has_rc_nodes)
{
double rc = DST_RCFILTER__R * DST_RCFILTER__C; double rc = DST_RCFILTER__R * DST_RCFILTER__C;
if (rc != context->rc) if (rc != context->rc)
{ {
context->rc = rc; context->rc = rc;
context->exponent = RC_CHARGE_EXP(rc); context->exponent = RC_CHARGE_EXP(rc);
} }
}
/************************************************************************/ /************************************************************************/
/* Next Value = PREV + (INPUT_VALUE - PREV)*(1-(EXP(-TIMEDELTA/RC))) */ /* Next Value = PREV + (INPUT_VALUE - PREV)*(1-(EXP(-TIMEDELTA/RC))) */
@ -1049,6 +1055,7 @@ static DISCRETE_RESET(dst_rcfilter)
{ {
struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context; struct dst_rcfilter_context *context = (struct dst_rcfilter_context *)node->context;
context->has_rc_nodes = node->input_is_node & 0x6;
context->rc = DST_RCFILTER__R * DST_RCFILTER__C; context->rc = DST_RCFILTER__R * DST_RCFILTER__C;
context->exponent = RC_CHARGE_EXP(context->rc); context->exponent = RC_CHARGE_EXP(context->rc);
context->vCap = 0; context->vCap = 0;