int cdCanvasPlay(cdCanvas* canvas, cdContext* context, int xmin, int xmax, int ymin, int ymax, void *data)
{
assert(context);
assert(canvas);
if (!_cdCheckCanvas(canvas) || !context || !context->cxPlay) return CD_ERROR;
/* the all can be 0 here, do not use cdCheckBoxSize */
if (xmin > xmax) _cdSwapInt(xmin, xmax);
if (ymin > ymax) _cdSwapInt(ymin, ymax);
return context->cxPlay(canvas, xmin, xmax, ymin, ymax, data);
}
void simFillHorizLine(cdSimulation* simulation, int xmin, int y, int xmax)
{
cdCanvas* canvas = simulation->canvas;
if(xmin > xmax)
_cdSwapInt(xmin, xmax);
switch(canvas->interior_style)
{
case CD_SOLID:
simulation->SolidLine(canvas, xmin,y,xmax, canvas->foreground);
break;
case CD_PATTERN:
simulation->PatternLine(canvas, xmin,xmax,y,canvas->pattern_w,
canvas->pattern +
canvas->pattern_w*CalcYPat(y, canvas->pattern_h));
break;
case CD_HATCH:
simulation->HatchLine(canvas, xmin,xmax,y,SimHatchBits[canvas->hatch_style][CalcYHatch(y, 7)]);
break;
case CD_STIPPLE:
simulation->StippleLine(canvas, xmin, xmax, y,
canvas->stipple_w,
canvas->stipple +
canvas->stipple_w*CalcYPat(y, canvas->stipple_h));
}
}
void cdCanvasScrollArea(cdCanvas* canvas, int xmin, int xmax, int ymin, int ymax, int dx, int dy)
{
assert(canvas);
if (!_cdCheckCanvas(canvas)) return;
if (!canvas->cxScrollArea) return;
if (!cdCheckBoxSize(&xmin, &xmax, &ymin, &ymax))
return;
if (dx == 0 && dy == 0)
return;
if (canvas->use_origin)
{
xmin += canvas->origin.x;
xmax += canvas->origin.x;
ymin += canvas->origin.y;
ymax += canvas->origin.y;
}
if (canvas->invert_yaxis)
{
dy = -dy;
ymin = _cdInvertYAxis(canvas, ymin);
ymax = _cdInvertYAxis(canvas, ymax);
_cdSwapInt(ymin, ymax);
}
canvas->cxScrollArea(canvas->ctxcanvas, xmin, xmax, ymin, ymax, dx, dy);
}
void cdCanvasBox(cdCanvas* canvas, int xmin, int xmax, int ymin, int ymax)
{
assert(canvas);
if (!_cdCheckCanvas(canvas)) return;
if (canvas->interior_style == CD_HOLLOW)
{
cdCanvasRect(canvas, xmin, xmax, ymin, ymax);
return;
}
if (!cdCheckBoxSize(&xmin, &xmax, &ymin, &ymax))
return;
if (canvas->use_origin)
{
xmin += canvas->origin.x;
xmax += canvas->origin.x;
ymin += canvas->origin.y;
ymax += canvas->origin.y;
}
if (canvas->invert_yaxis)
{
ymin = _cdInvertYAxis(canvas, ymin);
ymax = _cdInvertYAxis(canvas, ymax);
_cdSwapInt(ymin, ymax);
}
canvas->cxBox(canvas->ctxcanvas, xmin, xmax, ymin, ymax);
}
int simAddSegment(simLineSegment* segment, int x1, int y1, int x2, int y2, int *y_max, int *y_min)
{
if (x1==x2 && y1==y2)
return 0;
/* Make sure p2.y > p1.y */
if (y1 > y2)
{
_cdSwapInt(y1, y2);
_cdSwapInt(x1, x2);
segment->Swap = 1;
}
else
segment->Swap = 0;
segment->x1 = x1;
segment->y1 = y1;
segment->x2 = x2;
segment->y2 = y2;
segment->x = x2; /* initial value */
segment->DeltaY = y2 - y1;
segment->DeltaX = x2 - x1;
if (segment->DeltaX >= 0)
segment->XDir = -1; /* inverted from simLineThin since here is from p2 to p1 */
else
{
segment->XDir = 1;
segment->DeltaX = -segment->DeltaX; /* make DeltaX positive */
}
segment->ErrorAcc = 0; /* initialize the line error accumulator to 0 */
/* Is this an X-major or Y-major line? */
if (segment->DeltaY > segment->DeltaX)
{
if (segment->DeltaY==0) /* do not compute for horizontal segments */
return 1;
/* Y-major line; calculate 16-bit fixed-point fractional part of a
pixel that X advances each time Y advances 1 pixel, truncating the
result so that we won't overrun the endpoint along the X axis */
segment->ErrorInc = (unsigned short)(((unsigned long)segment->DeltaX << 16) / (unsigned long)segment->DeltaY);
}
else
{
if (segment->DeltaX==0) /* do not compute for vertical segments */
return 1;
/* It's an X-major line; calculate 16-bit fixed-point fractional part of a
pixel that Y advances each time X advances 1 pixel, truncating the
result to avoid overrunning the endpoint along the X axis */
segment->ErrorInc = (unsigned short)(((unsigned long)segment->DeltaY << 16) / (unsigned long)segment->DeltaX);
}
/* also calculates y_max and y_min of the polygon */
if (y2 > *y_max)
*y_max = y2;
if (y1 < *y_min)
*y_min = y1;
return 1;
}
