Merge branch 'master' of https://github.com/awgil/ffxiv_bossmod into wip

BossMod/Util/Bitmap.cs

@@ -0,0 +1,148 @@
+namespace BossMod;
+
+// utility for working with 2d 1bpp bitmaps
+// for easier compatibility with .bmp format, this is stored row-by-row (without any swizzle) with stride rounded up to 32 pixels (ie packing bits into dwords and requiring rows to start on dword boundary)
+public sealed class Bitmap
+{
+    public readonly int Width;
+    public readonly int Height;
+    public readonly int WordsPerRow;
+    public readonly uint[] Pixels;
+
+    public int BytesPerRow => WordsPerRow << 2;
+    public int CoordToIndex(int x, int y) => y * WordsPerRow + (x >> 5);
+    public uint CoordToMask(int x) => 1u << (x & 31);
+    public ref uint WordAt(int x, int y) => ref Pixels[CoordToIndex(x, y)];
+
+    public bool this[int x, int y]
+    {
+        get => (WordAt(x, y) & CoordToMask(x)) != 0;
+        set
+        {
+            if (value)
+                WordAt(x, y) |= CoordToMask(x);
+            else
+                WordAt(x, y) &= ~CoordToMask(x);
+        }
+    }
+
+    public Bitmap(int width, int height)
+    {
+        Width = width;
+        Height = height;
+        WordsPerRow = (width + 31) >> 5;
+        Pixels = new uint[height * WordsPerRow];
+    }
+
+    public Bitmap Clone()
+    {
+        var res = new Bitmap(Width, Height);
+        Array.Copy(Pixels, res.Pixels, Pixels.Length);
+        return res;
+    }
+
+    // copy a rectangle from source bitmap into current bitmap
+    // any out-of-range accesses are ignored: actual copied region is intersection of source data, copy rect and dest rect
+    public void CopyRegion(Bitmap source, int sourceX, int sourceY, int sourceWidth, int sourceHeight, int destX, int destY)
+    {
+        var offX = destX - sourceX;
+        var offY = destY - sourceY;
+        ClampRect(ref sourceX, ref sourceY, ref sourceWidth, ref sourceHeight, 0, 0, source.Width, source.Height, 0, 0);
+        ClampRect(ref sourceX, ref sourceY, ref sourceWidth, ref sourceHeight, 0, 0, Width, Height, offX, offY);
+        if (sourceWidth <= 0)
+            return; // nothing to copy
+
+        // note: this could be optimized if needed...
+        var maxX = sourceX + sourceWidth;
+        var maxY = sourceY + sourceHeight;
+        for (int y = sourceY; y < maxY; ++y)
+        {
+            for (int x = sourceX; x < maxX; ++x)
+            {
+                this[x + offX, y + offY] = source[x, y];
+            }
+        }
+    }
+
+    // upsample a region from source bitmap into current bitmap: each source pixel is converted into 2x2 destination pixels of same value
+    // note: if dest x/y are odd, they are rounded down
+    public void UpsampleRegion(Bitmap source, int sourceX, int sourceY, int sourceWidth, int sourceHeight, int destX, int destY)
+    {
+        // work in lower-resolution coordinates
+        destX >>= 1;
+        destY >>= 1;
+        var offX = destX - sourceX;
+        var offY = destY - sourceY;
+        ClampRect(ref sourceX, ref sourceY, ref sourceWidth, ref sourceHeight, 0, 0, source.Width, source.Height, 0, 0);
+        ClampRect(ref sourceX, ref sourceY, ref sourceWidth, ref sourceHeight, 0, 0, Width >> 1, Height >> 1, offX, offY);
+
+        if (sourceWidth <= 0)
+            return; // nothing to copy
+
+        // note: this could be optimized if needed...
+        var maxX = sourceX + sourceWidth;
+        var maxY = sourceY + sourceHeight;
+        for (int y = sourceY; y < maxY; ++y)
+        {
+            for (int x = sourceX; x < maxX; ++x)
+            {
+                this[(x + offX) << 1, (y + offY) << 1] = this[((x + offX) << 1) + 1, (y + offY) << 1] = this[(x + offX) << 1, ((y + offY) << 1) + 1] = this[((x + offX) << 1) + 1, ((y + offY) << 1) + 1] = source[x, y];
+            }
+        }
+    }
+
+    // downsample a region from source bitmap into current bitmap; each 2x2 group of source pixels are copied into destination pixel if equal, otherwise destination is set to fallback value
+    // note: if source x/y/w/h are odd, they are rounded down
+    public void DownsampleRegion(Bitmap source, int sourceX, int sourceY, int sourceWidth, int sourceHeight, int destX, int destY, bool fallback)
+    {
+        // work in lower-resolution coordinates
+        sourceX >>= 1;
+        sourceY >>= 1;
+        sourceWidth >>= 1;
+        sourceHeight >>= 1;
+        var offX = destX - sourceX;
+        var offY = destY - sourceY;
+        ClampRect(ref sourceX, ref sourceY, ref sourceWidth, ref sourceHeight, 0, 0, source.Width >> 1, source.Height >> 1, 0, 0);
+        ClampRect(ref sourceX, ref sourceY, ref sourceWidth, ref sourceHeight, 0, 0, Width, Height, offX, offY);
+
+        if (sourceWidth <= 0)
+            return; // nothing to copy
+
+        // note: this could be optimized if needed...
+        var maxX = sourceX + sourceWidth;
+        var maxY = sourceY + sourceHeight;
+        for (int y = sourceY; y < maxY; ++y)
+        {
+            for (int x = sourceX; x < maxX; ++x)
+            {
+                var v = source[x << 1, y << 1];
+                if (v != source[(x << 1) + 1, y << 1] || v != source[x << 1, (y << 1) + 1] || v != source[(x << 1) + 1, (y << 1) + 1])
+                    v = fallback;
+                this[x, y] = v;
+            }
+        }
+    }
+
+    // modify rect (x,y,w,h) so that, if offset by (dx,dy), it is clamped to rect (cx,cy,cw,ch)
+    private static void ClampRect(ref int x, ref int y, ref int w, ref int h, int cx, int cy, int cw, int ch, int dx, int dy)
+    {
+        var offX = x + dx - cx; // offset of left border from clip rect
+        if (offX < 0)
+        {
+            x -= offX;
+            w += offX;
+        }
+        var offY = y + dy - cy;
+        if (offY < 0)
+        {
+            y -= offY;
+            h += offY;
+        }
+        var maxW = cx + cw - (x + dx); // maximal width that rect can have so that when offset it doesn't extend past right border
+        if (w > maxW)
+            w = maxW;
+        var maxH = cy + ch - (y + dy);
+        if (h > maxH)
+            h = maxH;
+    }
+}