//按列逐行扫描
private void ScanLinePerRow(VertexOut left, VertexOut right, BaseShader shader)
{
VertexOut current;
int length = (int)right.posProjective.x - (int)left.posProjective.x;
if (length == 0)
{
return;
}
for (int i = 0; i <= length; i++)
{
float weight = (float)i / length;
current = LerpVertexOut(left, right, weight);
if (shader.ZTest == true)
{
if (current.posProjective.z >= 0.5f &&
current.posProjective.z > backBuffer.GetDepth((int)current.posProjective.x, (int)current.posProjective.y))
{
continue;
}
}
if (shader.ZWrite == true)
{
backBuffer.DrawDepth((int)current.posProjective.x, (int)current.posProjective.y, current.posProjective.z);
}
current.posProjective.x = left.posProjective.x + i;
current.posProjective.y = left.posProjective.y;
//透视纹理处理
shader.ProjectedMapRestore(current);
//片段着色
backBuffer.DrawPixel((int)current.posProjective.x, (int)current.posProjective.y, shader.FragmentShader(current));
}
}
