/* polygon:
* Draws a filled polygon with an arbitrary number of corners. Pass the
* number of vertices, then an array containing a series of x, y points
* (a total of vertices*2 values).
*/
void _soft_polygon(BITMAP *bmp, int vertices, AL_CONST int *points, int color)
{
int c;
int top = INT_MAX;
int bottom = INT_MIN;
AL_CONST int *i1, *i2;
POLYGON_EDGE *edge, *next_edge;
POLYGON_EDGE *active_edges = NULL;
POLYGON_EDGE *inactive_edges = NULL;
ASSERT(bmp);
/* allocate some space and fill the edge table */
_grow_scratch_mem(sizeof(POLYGON_EDGE) * vertices);
edge = (POLYGON_EDGE *)_scratch_mem;
i1 = points;
i2 = points + (vertices-1) * 2;
for (c=0; c<vertices; c++) {
fill_edge_structure(edge, i1, i2);
if (edge->bottom >= edge->top) {
if (edge->top < top)
top = edge->top;
if (edge->bottom > bottom)
bottom = edge->bottom;
inactive_edges = _add_edge(inactive_edges, edge, FALSE);
edge++;
}
i2 = i1;
i1 += 2;
}
if (bottom >= bmp->cb)
bottom = bmp->cb-1;
acquire_bitmap(bmp);
/* for each scanline in the polygon... */
for (c=top; c<=bottom; c++) {
int hid = 0;
int b1 = 0;
int e1 = 0;
int up = 0;
int draw = 0;
int e;
/* check for newly active edges */
edge = inactive_edges;
while ((edge) && (edge->top == c)) {
next_edge = edge->next;
inactive_edges = _remove_edge(inactive_edges, edge);
active_edges = _add_edge(active_edges, edge, TRUE);
edge = next_edge;
}
/* draw horizontal line segments */
edge = active_edges;
while (edge) {
e = edge->w;
if (edge->bottom != c) {
up = 1 - up;
}
else {
e = edge->w >> 1;
}
if (edge->top == c) {
e = edge->w >> 1;
}
if ((draw < 1) && (up >= 1)) {
b1 = (edge->x + e) >> POLYGON_FIX_SHIFT;
}
else if (draw >= 1) {
void CSurface8::Polygon(int iNum, int *ipVtx, int iCol) {
// Variables for polygon drawer
int c, x1, x2, y;
int top = INT_MAX;
int bottom = INT_MIN;
int *i1, *i2;
CPolyEdge *edge, *next_edge, *edgebuf;
CPolyEdge *active_edges = NULL;
CPolyEdge *inactive_edges = NULL;
BOOL use_qpb = FALSE;
// Poly Buf
if (iNum <= QuickPolyBufSize) {
edgebuf = QuickPolyBuf;
use_qpb = TRUE;
} else if (!(edgebuf = new CPolyEdge[iNum])) {
return;
}
// Fill the edge table
edge = edgebuf;
i1 = ipVtx;
i2 = ipVtx + (iNum - 1) * 2;
for (c = 0; c < iNum; c++) {
if (i1[1] != i2[1]) {
fill_edge_structure(edge, i1, i2);
if (edge->bottom >= edge->y) {
if (edge->y < top) top = edge->y;
if (edge->bottom > bottom) bottom = edge->bottom;
inactive_edges = add_edge(inactive_edges, edge, FALSE);
edge++;
}
}
i2 = i1;
i1 += 2;
}
// For each scanline in the polygon...
for (c = top; c <= bottom; c++) {
// Check for newly active edges
edge = inactive_edges;
while ((edge) && (edge->y == c)) {
next_edge = edge->next;
inactive_edges = remove_edge(inactive_edges, edge);
active_edges = add_edge(active_edges, edge, TRUE);
edge = next_edge;
}
// Draw horizontal line segments
edge = active_edges;
while ((edge) && (edge->next)) {
x1 = edge->x >> POLYGON_FIX_SHIFT;
x2 = (edge->next->x + edge->next->w) >> POLYGON_FIX_SHIFT;
y = c;
// Fix coordinates
if (x1 > x2) Swap(x1, x2);
// Set line
for (int xcnt = x2 - x1; xcnt >= 0; xcnt--) SetPix(x1 + xcnt, y, iCol);
edge = edge->next->next;
}
// Update edges, sorting and removing dead ones
edge = active_edges;
while (edge) {
next_edge = edge->next;
if (c >= edge->bottom) {
active_edges = remove_edge(active_edges, edge);
} else {
edge->x += edge->dx;
while ((edge->prev) &&
(edge->x + edge->w / 2 < edge->prev->x + edge->prev->w / 2)) {
if (edge->next) edge->next->prev = edge->prev;
edge->prev->next = edge->next;
edge->next = edge->prev;
edge->prev = edge->prev->prev;
edge->next->prev = edge;
if (edge->prev)
edge->prev->next = edge;
else
active_edges = edge;
}
}
edge = next_edge;
}
}
// Clear scratch memory
if (!use_qpb) delete[] edgebuf;
}
