public MyScreenCanvas GetCanvasPage(int hPageNum, int vPageNum)
{
int j = cachePages.Count;
for (int i = j - 1; i > -1; i--)
{
MyScreenCanvas page = cachePages[i];
if (page.IsPageNumber(hPageNum, vPageNum))
{
cachePages.RemoveAt(i);
if (page.DimensionInvalid)
{
page.Reset(hPageNum, vPageNum, eachPageWidth, eachPageHeight);
page.IsUnused = false;
}
return(page);
}
}
if (j >= numOfCachePages)
{
MyScreenCanvas page = cachePages[0];
cachePages.RemoveAt(0);
page.IsUnused = false;
if (page.DimensionInvalid)
{
page.Reset(hPageNum, vPageNum, eachPageWidth, eachPageHeight);
}
else
{
page.Reuse(hPageNum, vPageNum);
}
Rectangle rect = page.Rect;
page.Invalidate(rect);
return(page);
}
else
{
return(new MyScreenCanvas(gfxPlatform,
hPageNum,
vPageNum,
hPageNum * eachPageWidth,
eachPageHeight * vPageNum,
eachPageWidth,
eachPageHeight));
}
}
public void CalculateCanvasPages(int viewportX, int viewportY, int viewportWidth, int viewportHeight)
{
int firstVerticalPageNum = viewportY / physicalCanvasCollection.EachPageHeight;
int firstHorizontalPageNum = viewportX / physicalCanvasCollection.EachPageWidth;
render_parts = PAGE_A;
if (pageA == null)
{
pageA = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum, firstVerticalPageNum);
}
else
{
if (!pageA.IsPageNumber(firstHorizontalPageNum, firstVerticalPageNum))
{
physicalCanvasCollection.ReleasePage(pageA);
pageA = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum, firstVerticalPageNum);
}
}
if (pageA.Right >= viewportX + viewportWidth)
{
if (pageC != null)
{
physicalCanvasCollection.ReleasePage(pageC);
pageC = null;
}
}
else
{
if (pageC == null)
{
pageC = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum + 1, firstVerticalPageNum);
}
else
{
if (!pageC.IsPageNumber(firstHorizontalPageNum + 1, firstVerticalPageNum))
{
physicalCanvasCollection.ReleasePage(pageC);
pageC = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum + 1, firstVerticalPageNum);
}
}
render_parts |= PAGE_AC;
}
if (pageA.Bottom >= viewportY + viewportHeight)
{
if (pageB != null)
{
physicalCanvasCollection.ReleasePage(pageB);
pageB = null;
}
}
else
{
render_parts |= PAGE_AB;
if (pageB == null)
{
pageB = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum, firstVerticalPageNum + 1);
}
else
{
if (!pageB.IsPageNumber(firstHorizontalPageNum, firstVerticalPageNum + 1))
{
physicalCanvasCollection.ReleasePage(pageB);
pageB = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum, firstVerticalPageNum + 1);
}
}
if (pageC != null)
{
render_parts = PAGE_ABCD;
if (pageD == null)
{
pageD = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum + 1, firstVerticalPageNum + 1);
}
else
{
if (!pageD.IsPageNumber(firstHorizontalPageNum + 1, firstVerticalPageNum + 1))
{
physicalCanvasCollection.ReleasePage(pageD);
pageD = physicalCanvasCollection.GetCanvasPage(firstHorizontalPageNum + 1, firstVerticalPageNum + 1);
}
}
}
else
{
if (pageD != null)
{
physicalCanvasCollection.ReleasePage(pageD);
pageD = null;
}
}
}
}
