Implement board textures in XBoard

The -darkBackTextureFile and -liteBackTextureFile options now wrk in
XBoard too, for loading a pixmap that will be used to cut out the dark
and light square backgrounds. The cutting algorithm is such that the
pixmap image is completely restored if the size was that of the total
board (e.g. a drawing of a Xiangqi board).

diff --git a/xboard.c b/xboard.c
index 80e622e..f975e95 100644 (file)
--- a/xboard.c
+++ b/xboard.c
@@ -248,6 +248,7 @@ RETSIGTYPE TermSizeSigHandler P((int sig));
 void CreateGCs P((void));
 void CreateXIMPieces P((void));
 void CreateXPMPieces P((void));
+void CreateXPMBoard P((char *s, int n));
 void CreatePieces P((void));
 void CreatePieceMenus P((void));
 Widget CreateMenuBar P((Menu *mb));
@@ -562,7 +563,8 @@ Pixmap pieceBitmap2[2][(int)BlackPawn+4];       /* [HGM] pieces */
 Pixmap xpmPieceBitmap[4][(int)BlackPawn];      /* LL, LD, DL, DD actually used*/
 Pixmap xpmPieceBitmap2[4][(int)BlackPawn+4];   /* LL, LD, DL, DD set to select from */
 Pixmap xpmLightSquare, xpmDarkSquare, xpmJailSquare;
-int useImages, useImageSqs;
+Pixmap xpmBoardBitmap[2];
+int useImages, useImageSqs, useTexture, textureW[2], textureH[2];
 XImage *ximPieceBitmap[4][(int)BlackPawn+4];   /* LL, LD, DL, DD */
 Pixmap ximMaskPm[(int)BlackPawn];               /* clipmasks, used for XIM pieces */
 Pixmap ximMaskPm2[(int)BlackPawn+4];            /* clipmasks, used for XIM pieces */
@@ -2543,6 +2545,8 @@ XBoard square size (hint): %d\n\
       CreatePieces();
     } else {
       CreateXPMPieces();
+      CreateXPMBoard(appData.liteBackTextureFile, 1);
+      CreateXPMBoard(appData.darkBackTextureFile, 0);
     }
 #else
     CreateXIMPieces();
@@ -3400,6 +3404,16 @@ void CreateXIMPieces()
 }
 
 #if HAVE_LIBXPM
+void CreateXPMBoard(char *s, int kind)
+{
+    XpmAttributes attr;
+    attr.valuemask = 0;
+    if(s == NULL || *s == 0 || *s == '*') return;
+    if (XpmReadFileToPixmap(xDisplay, xBoardWindow, s, &(xpmBoardBitmap[kind]), NULL, &attr) == 0) {
+       useTexture |= kind + 1; textureW[kind] = attr.width; textureH[kind] = attr.height;
+    }
+}
+
 void CreateXPMPieces()
 {
     int piece, kind, r;
@@ -4066,11 +4080,34 @@ ClearPremoveHighlights()
   SetPremoveHighlights(-1, -1, -1, -1);
 }
 
-static void BlankSquare(x, y, color, piece, dest)
-     int x, y, color;
+static int CutOutSquare(x, y, x0, y0, kind)
+     int x, y, *x0, *y0, kind;
+{
+    int W = BOARD_WIDTH, H = BOARD_HEIGHT;
+    int nx = x/(squareSize + lineGap), ny = y/(squareSize + lineGap);
+    *x0 = 0; *y0 = 0;
+    if(textureW[kind] < squareSize || textureH[kind] < squareSize) return 0;
+    if(textureW[kind] < W*squareSize)
+       *x0 = (textureW[kind] - squareSize) * nx/(W-1);
+    else
+       *x0 = textureW[kind]*nx / W + (textureW[kind] - W*squareSize) / (2*W);
+    if(textureH[kind] < H*squareSize)
+       *y0 = (textureH[kind] - squareSize) * ny/(H-1);
+    else
+       *y0 = textureH[kind]*ny / H + (textureH[kind] - H*squareSize) / (2*H);
+    return 1;
+}
+
+static void BlankSquare(x, y, color, piece, dest, fac)
+     int x, y, color, fac;
      ChessSquare piece;
      Drawable dest;
-{
+{   // [HGM] extra param 'fac' for forcing destination to (0,0) for copying to animation buffer
+    int x0, y0;
+    if (useImages && color != 2 && (useTexture & color+1) && CutOutSquare(x, y, &x0, &y0, color)) {
+       XCopyArea(xDisplay, xpmBoardBitmap[color], dest, wlPieceGC, x0, y0,
+                 squareSize, squareSize, x*fac, y*fac);
+    } else
     if (useImages && useImageSqs) {
        Pixmap pm;
        switch (color) {
@@ -4086,7 +4123,7 @@ static void BlankSquare(x, y, color, piece, dest)
            break;
        }
        XCopyArea(xDisplay, pm, dest, wlPieceGC, 0, 0,
-                 squareSize, squareSize, x, y);
+                 squareSize, squareSize, x*fac, y*fac);
     } else {
        GC gc;
        switch (color) {
@@ -4101,7 +4138,7 @@ static void BlankSquare(x, y, color, piece, dest)
            gc = jailSquareGC;
            break;
        }
-       XFillRectangle(xDisplay, dest, gc, x, y, squareSize, squareSize);
+       XFillRectangle(xDisplay, dest, gc, x*fac, y*fac, squareSize, squareSize);
     }
 }
 
@@ -4194,7 +4231,7 @@ static void colorDrawPieceImage(piece, square_color, x, y, dest)
      int square_color, x, y;
      Drawable dest;
 {
-    int kind;
+    int kind, p = piece;
 
     switch (square_color) {
       case 1: /* light */
@@ -4217,6 +4254,14 @@ static void colorDrawPieceImage(piece, square_color, x, y, dest)
        break;
     }
     if(appData.upsideDown && flipView) kind ^= 2; // swap white and black pieces
+    if(useTexture & square_color+1) {
+        BlankSquare(x, y, square_color, piece, dest, 1); // erase previous contents with background
+       XSetClipMask(xDisplay, wlPieceGC, xpmMask[p]);
+       XSetClipOrigin(xDisplay, wlPieceGC, x, y);
+       XCopyArea(xDisplay, xpmPieceBitmap[kind][piece], dest, wlPieceGC, 0, 0, squareSize, squareSize, x, y);
+       XSetClipMask(xDisplay, wlPieceGC, None);
+       XSetClipOrigin(xDisplay, wlPieceGC, 0, 0);
+    } else
     XCopyArea(xDisplay, xpmPieceBitmap[kind][piece],
              dest, wlPieceGC, 0, 0,
              squareSize, squareSize, x, y);
@@ -4298,7 +4343,7 @@ void DrawSquare(row, column, piece, do_flash)
                  column == BOARD_LEFT-1 ||  column == BOARD_RGHT
               || (column == BOARD_LEFT-2 && row < BOARD_HEIGHT-gameInfo.holdingsSize)
                  || (column == BOARD_RGHT+1 && row >= gameInfo.holdingsSize) ) {
-                       BlankSquare(x, y, 2, EmptySquare, xBoardWindow);
+                       BlankSquare(x, y, 2, EmptySquare, xBoardWindow, 1);
 
                        // [HGM] print piece counts next to holdings
                        string[1] = NULLCHAR;
@@ -4330,7 +4375,7 @@ void DrawSquare(row, column, piece, do_flash)
                        }
     } else {
            if (piece == EmptySquare || appData.blindfold) {
-                       BlankSquare(x, y, square_color, piece, xBoardWindow);
+                       BlankSquare(x, y, square_color, piece, xBoardWindow, 1);
            } else {
                        drawfunc = ChooseDrawFunc();
                        if (do_flash && appData.flashCount > 0) {
@@ -4340,7 +4385,7 @@ void DrawSquare(row, column, piece, do_flash)
                                        XSync(xDisplay, False);
                                        do_flash_delay(flash_delay);
 
-                                       BlankSquare(x, y, square_color, piece, xBoardWindow);
+                                       BlankSquare(x, y, square_color, piece, xBoardWindow, 1);
                                        XSync(xDisplay, False);
                                        do_flash_delay(flash_delay);
                            }
@@ -8765,7 +8810,7 @@ BeginAnimation(anim, piece, startColor, start)
   Pixmap mask;
 
   /* The old buffer is initialised with the start square (empty) */
-  BlankSquare(0, 0, startColor, EmptySquare, anim->saveBuf);
+  BlankSquare(start->x, start->y, startColor, EmptySquare, anim->saveBuf, 0);
   anim->prevFrame = *start;
 
   /* The piece will be drawn using its own bitmap as a matte   */
@@ -9049,7 +9094,7 @@ DrawDragPiece ()
      it's being dragged around the board. So we erase the square
      that the piece is on and draw it at the last known drag point. */
   BlankSquare(player.startSquare.x, player.startSquare.y,
-               player.startColor, EmptySquare, xBoardWindow);
+               player.startColor, EmptySquare, xBoardWindow, 1);
   AnimationFrame(&player, &player.prevFrame, player.dragPiece);
   damage[0][player.startBoardY][player.startBoardX] = TRUE;
 }