/*!
* \brief Free the memory used by a net.
*/
void
FreeNetListMemory (NetListType *Netlist) {
if (Netlist) {
NET_LOOP (Netlist);
{
FreeNetMemory (net);
}
END_LOOP;
free (Netlist->Net);
memset (Netlist, 0, sizeof (NetListType));
}
}
/*
* copy all connections from one net into another
* and then remove the first net from its netlist
*/
static void
TransferNet (NetListTypePtr Netl, NetTypePtr SourceNet, NetTypePtr DestNet)
{
ConnectionTypePtr conn;
CONNECTION_LOOP (SourceNet);
{
conn = GetConnectionMemory (DestNet);
*conn = *connection;
}
END_LOOP;
DestNet->Style = SourceNet->Style;
/* free the connection memory */
FreeNetMemory (SourceNet);
/* remove SourceNet from its netlist */
*SourceNet = Netl->Net[--(Netl->NetN)];
/* zero out old garbage */
memset (&Netl->Net[Netl->NetN], 0, sizeof (NetType));
}
/*!
* \brief Copy all connections from one net into another and then remove
* the first net from its netlist.
*/
static void
TransferNet (NetListType *Netl, NetType *SourceNet, NetType *DestNet)
{
ConnectionType *conn;
/* It would be worth checking if SourceNet is NULL here to avoid a segfault. Seb James. */
CONNECTION_LOOP (SourceNet);
{
conn = GetConnectionMemory (DestNet);
*conn = *connection;
}
END_LOOP;
DestNet->Style = SourceNet->Style;
/* free the connection memory */
FreeNetMemory (SourceNet);
/* remove SourceNet from its netlist */
*SourceNet = Netl->Net[--(Netl->NetN)];
/* zero out old garbage */
memset (&Netl->Net[Netl->NetN], 0, sizeof (NetType));
}
/*!
* \brief Draw a rat net (tree) having the shortest lines.
*
* This also frees the subnet memory as they are consumed.
*
* \note The \c Netl we are passed is NOT the main netlist - it's the
* connectivity for ONE net.
* It represents the CURRENT connectivity state for the net, with each
* Netl->Net[N] representing one copper-connected subset of the net.
*
* Everything inside the NetList Netl should be connected together.
*
* Each Net in \c Netl is a group of Connections which are already
* connected together somehow, either by real wires or by rats we've
* already drawn.
*
* Each Connection is a vertex within that blob of connected items.
*
* This loop finds the closest vertex pairs between each blob and draws
* rats that merge the blobs until there's just one big blob.
*
* Just to clarify, with some examples:
*
* Each \c Netl is one full net from a netlist, like from gnetlist.
*
* Each Netl->Net[N] is a subset of that net that's already
* physically connected on the pcb.
*
* So a new design with no traces yet, would have a huge list of Net[N],
* each with one pin in it.
*
* A fully routed design would have one Net[N] with all the pins
* (for that net) in it.
*/
static bool
DrawShortestRats (NetListType *Netl, void (*funcp) (register ConnectionType *, register ConnectionType *, register RouteStyleType *))
{
RatType *line;
register float distance, temp;
register ConnectionType *conn1, *conn2, *firstpoint, *secondpoint;
PolygonType *polygon;
bool changed = false;
bool havepoints;
Cardinal n, m, j;
NetType *next, *subnet, *theSubnet = NULL;
/* This is just a sanity check, to make sure we're passed
* *something*.
*/
if (!Netl || Netl->NetN < 1)
return false;
/*
* We keep doing this do/while loop until everything's connected.
* I.e. once per rat we add.
*/
distance = 0.0;
havepoints = true; /* so we run the loop at least once */
while (Netl->NetN > 1 && havepoints)
{
/* This is the top of the "find one rat" logic. */
havepoints = false;
firstpoint = secondpoint = NULL;
/* Test Net[0] vs Net[N] for N=1..max. Find the shortest
distance between any two points in different blobs. */
subnet = &Netl->Net[0];
for (j = 1; j < Netl->NetN; j++)
{
/*
* Scan between Net[0] blob (subnet) and Net[N] blob (next).
* Note the shortest distance we find.
*/
next = &Netl->Net[j];
for (n = subnet->ConnectionN - 1; n != -1; n--)
{
conn1 = &subnet->Connection[n];
for (m = next->ConnectionN - 1; m != -1; m--)
{
conn2 = &next->Connection[m];
/*
* At this point, conn1 and conn2 are two pins in
* different blobs of the same net. See how far
* apart they are, and if they're "closer" than what
* we already have.
*/
/*
* Prefer to connect Connections over polygons to the
* polygons (ie assume the user wants a via to a plane,
* not a daisy chain). Further prefer to pick an existing
* via in the Net to make that connection.
*/
if (conn1->type == POLYGON_TYPE &&
(polygon = (PolygonType *)conn1->ptr2) &&
!(distance == 0 &&
firstpoint && firstpoint->type == VIA_TYPE) &&
IsPointInPolygonIgnoreHoles (conn2->X, conn2->Y, polygon))
{
distance = 0;
firstpoint = conn2;
secondpoint = conn1;
theSubnet = next;
havepoints = true;
}
else if (conn2->type == POLYGON_TYPE &&
(polygon = (PolygonType *)conn2->ptr2) &&
!(distance == 0 &&
firstpoint && firstpoint->type == VIA_TYPE) &&
IsPointInPolygonIgnoreHoles (conn1->X, conn1->Y, polygon))
{
distance = 0;
firstpoint = conn1;
secondpoint = conn2;
theSubnet = next;
havepoints = true;
}
else if ((temp = SQUARE (conn1->X - conn2->X) +
SQUARE (conn1->Y - conn2->Y)) < distance || !firstpoint)
{
distance = temp;
firstpoint = conn1;
secondpoint = conn2;
theSubnet = next;
havepoints = true;
}
}
}
}
/*
* If HAVEPOINTS is true, we've found a pair of points in two
* separate blobs of the net, and need to connect them together.
*/
if (havepoints)
{
if (funcp)
{
(*funcp) (firstpoint, secondpoint, subnet->Style);
}
else
{
/* found the shortest distance subnet, draw the rat */
if ((line = CreateNewRat (PCB->Data,
firstpoint->X, firstpoint->Y,
secondpoint->X, secondpoint->Y,
firstpoint->group, secondpoint->group,
Settings.RatThickness,
NoFlags ())) != NULL)
{
if (distance == 0)
SET_FLAG (VIAFLAG, line);
AddObjectToCreateUndoList (RATLINE_TYPE, line, line, line);
DrawRat (line);
changed = true;
}
}
/* copy theSubnet into the current subnet */
TransferNet (Netl, theSubnet, subnet);
}
}
/* presently nothing to do with the new subnet */
/* so we throw it away and free the space */
FreeNetMemory (&Netl->Net[--(Netl->NetN)]);
/* Sadly adding a rat line messes up the sorted arrays in connection finder */
/* hace: perhaps not necessarily now that they aren't stored in normal layers */
if (changed)
{
FreeConnectionLookupMemory ();
InitConnectionLookup ();
}
return (changed);
}
