private void HorizontalEdgeTriangle(Vector2 apex, float leftBottomX, float rightBottomX, float bottomY, bool skipBottomEdge = false, bool interpolate = true)
{
if (skipBottomEdge && MathF.Abs(apex.Y - bottomY) < 1f)
{
return;
}
bool isUpward = apex.Y > bottomY;
float invHeight = 1f / (isUpward ? apex.Y - bottomY : apex.Y - bottomY);
float leftInvSlope = (apex.X - leftBottomX) * invHeight;
float rightInvSlope = (apex.X - rightBottomX) * invHeight;
Vector2Int result = Vector2Int.Zero;
int endX, endY;
if (isUpward)
{
endY = skipBottomEdge ? (int)bottomY + 1 : (int)bottomY;
result.Y = (int)apex.Y;
leftBottomX = rightBottomX = apex.X;
}
else
{
endY = (int)apex.Y;
if (skipBottomEdge)
{
result.Y = (int)bottomY - 1;
leftBottomX -= leftInvSlope;
rightBottomX -= rightInvSlope;
}
else
{
result.Y = (int)bottomY;
}
}
for (; result.Y >= endY; result.Y--)
{
endX = (int)rightBottomX;
for (result.X = (int)leftBottomX; result.X <= endX; result.X++)
{
if (interpolate)
{
RasterizerEntry.OutputRasterization(result, TriangleInterpolator_Horizontal.InterpolatedValues);
TriangleInterpolator_Horizontal.IncrementStep();
}
else
{
RasterizerEntry.OutputRasterization(result);
}
}
leftBottomX -= leftInvSlope;
rightBottomX -= rightInvSlope;
if (interpolate)
{
TriangleInterpolator_Vertical.IncrementStep();
}
}
}
public void Rasterize(LinePrimitive *linePtr)
{
Vector2 *verticesPtr = linePtr->CoordsPtr;
float ** verticesDataPtr = linePtr->VerticesDataPtr;
int verticesDataCount = linePtr->VerticesDataCount;
Vector2 from = verticesPtr[0] * Resolution, to = verticesPtr[1] * Resolution;
float xSub = to.X - from.X,
ySub = to.Y - from.Y;
//0: X-major 1:Y-major
int dir;
int dirStep, otherDirStep;
float slopeAbs;
if (Math.Abs(xSub) >= Math.Abs(ySub))
{
dir = 0;
}
else
{
dir = 1;
float temp = xSub;
xSub = ySub;
ySub = temp;
}
dirStep = Math.Sign(xSub);
otherDirStep = Math.Sign(ySub);
slopeAbs = Math.Abs(ySub / xSub);
bool ifInterpolate = verticesDataCount > 0;
if (ifInterpolate)
{
LineInterpolator.SetInterpolation(verticesDataPtr[0], verticesDataPtr[1], verticesDataCount, Math.Abs(xSub));
}
Vector2Int resultPoint = new Vector2Int(JMath.RoundToInt(from.X), JMath.RoundToInt(from.Y));
if (resultPoint.X == Resolution.X)
{
resultPoint.X--;
}
if (resultPoint.Y == Resolution.Y)
{
resultPoint.Y--;
}
//End coordinate in Int
int end = JMath.RoundToInt(to[dir]);
for (float otherDirFrac = slopeAbs; resultPoint[dir] != end; otherDirFrac += slopeAbs, resultPoint[dir] += dirStep)
{
if (ifInterpolate)
{
RasterizerEntry.OutputRasterization(resultPoint, LineInterpolator.InterpolatedValues);
LineInterpolator.IncrementStep();
}
else
{
RasterizerEntry.OutputRasterization(resultPoint, LineInterpolator.InterpolatedValues);
}
if (otherDirFrac >= 1f)
{
resultPoint[1 - dir] += otherDirStep;
otherDirFrac--;
}
}
}
