/// <summary>
/// 绘制Texture2D
/// </summary>
/// <param name="texture">目标Texture2D</param>
/// <param name="transform">变换矩阵</param>
/// <param name="overlayColor">要叠加的颜色</param>
/// <param name="pivot">变换轴点</param>
/// <param name="mode">图像混合模式</param>
/// <returns></returns>
public Texture2DCombiner DrawTexture(Texture2D texture, Matrix4x4 transform, Color overlayColor, Vector2 pivot, MixMode mode = MixMode.Overlay)
{
var width = texture.width;
var height = texture.height;
PrepareTransform(ref transform, in pivot, in width, in height, out var area);
if (_renderCanvas == null)
{
var pixels = texture.GetPixels();
var canvasPixels = _canvas.GetPixels(area.x, area.y, area.width, area.height);
var areaX = area.xMax;
var areaY = area.yMax;
for (var i = area.y - 1; ++i < areaY;)
{
for (var j = area.x - 1; ++j < areaX;)
{
var position = (Vector2)transform.MultiplyPoint(new Vector2(j, i));
if (!position.x.InRange(0, width) || !position.y.InRange(0, height))
{
continue;
}
var canvasPixelIndex = j - area.x + (i - area.y) * area.width;
var origin = canvasPixels[canvasPixelIndex];
var target = BilinearInterpolation(position, pixels, width) * overlayColor;
canvasPixels[canvasPixelIndex] = MixColor(in origin, in target, mode);
}
}
_canvas.SetPixels(area.x, area.y, area.width, area.height, canvasPixels);
}
else
{
var kernel = GetKernel(mode);
_shader.SetVector(ShaderSizeName, new Vector4(area.x, area.y, width, height));
_shader.SetTexture(kernel, ShaderSourceName, texture);
_shader.SetVector(ShaderColorName, overlayColor);
_shader.SetMatrix(ShaderTransformName, transform);
var currentTexture = _renderCanvas.Active();
_shader.Dispatch(kernel, Mathf.CeilToInt(area.width / 24.0F), Mathf.CeilToInt(area.height / 24.0F), 1);
RenderTexture.active = currentTexture;
}
return(this);
}
