C++ (Cpp) Canvas::DrawMaskedBitmap示例

/*
** Draws the meter on the double buffer
**
*/
bool MeterImage::Draw(Gfx::Canvas& canvas)
{
	if (!Meter::Draw(canvas)) return false;

	if (m_Image.IsLoaded())
	{
		// Copy the image over the doublebuffer
		Bitmap* drawBitmap = m_Image.GetImage();

		int imageW = drawBitmap->GetWidth();
		int imageH = drawBitmap->GetHeight();
		
		if (imageW == 0 || imageH == 0 || m_W == 0 || m_H == 0) return true;

		Gdiplus::Rect meterRect = GetMeterRectPadding();

		int drawW = meterRect.Width;
		int drawH = meterRect.Height;

		bool hasMask = (m_Skin->GetUseD2D() && m_MaskImage.IsLoaded());
		if (hasMask)
		{
			Bitmap* maskBitmap = m_MaskImage.GetImage();

			imageW = maskBitmap->GetWidth();
			imageH = maskBitmap->GetHeight();
			int imageMW = drawBitmap->GetWidth();
			int imageMH = drawBitmap->GetHeight();

			int cropX = 0;
			int cropY = 0;
			int cropW = imageMW;
			int cropH = imageMH;

			REAL imageratio = imageMW / (REAL)imageMH;
			REAL meterRatio = meterRect.Width / (REAL)meterRect.Height;

			if (imageratio != meterRatio)
			{
				if (imageratio > meterRatio)
				{
					cropW = (int)(imageMH * meterRatio);
					cropX = (imageMW - cropW) / 2;
				}
				else
				{
					cropH = (int)(imageMW / meterRatio);
					cropY = (imageMH - cropH) / 2;
				}
			}

			canvas.DrawMaskedBitmap(drawBitmap, maskBitmap, meterRect, Rect(0, 0, imageW, imageH), Gdiplus::Rect(cropX, cropY, cropW, cropH));
		}

		else if (drawW == imageW && drawH == imageH &&
			m_ScaleMargins.left == 0 && m_ScaleMargins.top == 0 && m_ScaleMargins.right == 0 && m_ScaleMargins.bottom == 0)
		{
			canvas.DrawBitmap(drawBitmap, Rect(meterRect.X, meterRect.Y, drawW, drawH), Rect(0, 0, imageW, imageH));
		}
		else if (m_DrawMode == DRAWMODE_TILE)
		{
			Gdiplus::Graphics& graphics = canvas.BeginGdiplusContext();

			ImageAttributes imgAttr;
			imgAttr.SetWrapMode(WrapModeTile);

			Rect r(meterRect.X, meterRect.Y, drawW, drawH);
			graphics.DrawImage(drawBitmap, r, 0, 0, drawW, drawH, UnitPixel, &imgAttr);

			canvas.EndGdiplusContext();
		}
		else if (m_DrawMode == DRAWMODE_KEEPRATIO || m_DrawMode == DRAWMODE_KEEPRATIOANDCROP)
		{
			int cropX = 0;
			int cropY = 0;
			int cropW = imageW;
			int cropH = imageH;

			if (m_WDefined && m_HDefined)
			{
				REAL imageRatio = imageW / (REAL)imageH;
				REAL meterRatio = meterRect.Width / (REAL)meterRect.Height;

				if (imageRatio != meterRatio)
				{
					if (m_DrawMode == DRAWMODE_KEEPRATIO)
					{
						if (imageRatio > meterRatio)
						{
							drawH = meterRect.Width * imageH / imageW;
							meterRect.Y += (meterRect.Height - drawH) / 2;
						}
						else
						{
							drawW = meterRect.Height * imageW / imageH;
							meterRect.X += (meterRect.Width - drawW) / 2;
						}
					}
					else
					{
						if (imageRatio > meterRatio)
						{
							cropW = (int)(imageH * meterRatio);
							cropX = (imageW - cropW) / 2;
						}
						else
						{
							cropH = (int)(imageW / meterRatio);
							cropY = (imageH - cropH) / 2;
						}
					}
				}
			}

			Rect r(meterRect.X, meterRect.Y, drawW, drawH);
			canvas.DrawBitmap(drawBitmap, r, Rect(cropX, cropY, cropW, cropH));
		}
		else
		{
			const RECT& m = m_ScaleMargins;

			if (m.top > 0)
			{
				if (m.left > 0)
				{
					// Top-Left
					Rect r(meterRect.X, meterRect.Y, m.left, m.top);
					canvas.DrawBitmap(drawBitmap, r, Rect(0, 0, m.left, m.top));
				}

				// Top
				Rect r(meterRect.X + m.left, meterRect.Y, drawW - m.left - m.right, m.top);
				canvas.DrawBitmap(drawBitmap, r, Rect(m.left, 0, imageW - m.left - m.right, m.top));

				if (m.right > 0)
				{
					// Top-Right
					Rect r(meterRect.X + drawW - m.right, meterRect.Y, m.right, m.top);
					canvas.DrawBitmap(drawBitmap, r, Rect(imageW - m.right, 0, m.right, m.top));
				}
			}

			if (m.left > 0)
			{
				// Left
				Rect r(meterRect.X, meterRect.Y + m.top, m.left, drawH - m.top - m.bottom);
				canvas.DrawBitmap(drawBitmap, r, Rect(0, m.top, m.left, imageH - m.top - m.bottom));
			}

			// Center
			Rect r(meterRect.X + m.left, meterRect.Y + m.top, drawW - m.left - m.right, drawH - m.top - m.bottom);
			canvas.DrawBitmap(drawBitmap, r, Rect(m.left, m.top, imageW - m.left - m.right, imageH - m.top - m.bottom));

			if (m.right > 0)
			{
				// Right
				Rect r(meterRect.X + drawW - m.right, meterRect.Y + m.top, m.right, drawH - m.top - m.bottom);
				canvas.DrawBitmap(drawBitmap, r, Rect(imageW - m.right, m.top, m.right, imageH - m.top - m.bottom));
			}

			if (m.bottom > 0)
			{
				if (m.left > 0)
				{
					// Bottom-Left
					Rect r(meterRect.X, meterRect.Y + drawH - m.bottom, m.left, m.bottom);
					canvas.DrawBitmap(drawBitmap, r, Rect(0, imageH - m.bottom, m.left, m.bottom));
				}

				// Bottom
				Rect r(meterRect.X + m.left, meterRect.Y + drawH - m.bottom, drawW - m.left - m.right, m.bottom);
				canvas.DrawBitmap(drawBitmap, r, Rect(m.left, imageH - m.bottom, imageW - m.left - m.right, m.bottom));

				if (m.right > 0)
				{
					// Bottom-Right
					Rect r(meterRect.X + drawW - m.right, meterRect.Y + drawH - m.bottom, m.right, m.bottom);
					canvas.DrawBitmap(drawBitmap, r, Rect(imageW - m.right, imageH - m.bottom, m.right, m.bottom));
				}
			}
		}
	}

	return true;
}