Extend full-board textures by periodic tiling (XB)

[xboard.git] / draw.c

diff --git a/draw.c b/draw.c
index 6df1a13..4ad6887 100644 (file)
--- a/draw.c
+++ b/draw.c
@@ -269,6 +269,8 @@ ExposeRedraw (Option *graph, int x, int y, int w, int h)
     cairo_destroy(cr);
 }
 
+static int modV[2], modH[2];
+
 static void
 CreatePNGBoard (char *s, int kind)
 {
@@ -286,13 +288,14 @@ CreatePNGBoard (char *s, int kind)
            useTexture |= kind + 1; pngOriginalBoardBitmap[kind] = img;
            w = textureW[kind] = cairo_image_surface_get_width (img);
            h = textureH[kind] = cairo_image_surface_get_height (img);
-           n[kind] = 1.;
+           n[kind] = 1.; modV[kind] = modH[kind] = -1;
            while((q = strchr(p+1, '-'))) p = q; // find last '-'
            if(strlen(p) < 11 && sscanf(p, "-%dx%d.pn%c", &f, &r, &c) == 3 && c == 'g') {
                if(f == 0 || r == 0) f = BOARD_WIDTH, r = BOARD_HEIGHT; // 0x0 means 'fits any', so make it fit
                textureW[kind] = (w*BOARD_WIDTH)/f; // sync cutting locations with square pattern
                textureH[kind] = (h*BOARD_HEIGHT)/r;
                n[kind] = r*squareSize/h; // scale to make it fit exactly vertically
+               modV[kind] = r; modH[kind] = f;
            } else
            if((p = strstr(s, "xq")) && (p == s || p[-1] == '/')) { // assume full-board image for Xiangqi
                while(0.8*squareSize*BOARD_WIDTH > n[kind]*w || 0.8*squareSize*BOARD_HEIGHT > n[kind]*h) n[kind]++;
@@ -672,6 +675,7 @@ CutOutSquare (int x, int y, int *x0, int *y0, int  kind)
     int nx = x/(squareSize + lineGap), ny = y/(squareSize + lineGap);
     *x0 = 0; *y0 = 0;
     if(textureW[kind] < squareSize || textureH[kind] < squareSize) return 0;
+    if(modV[kind] > 0) nx %= modH[kind], ny %= modV[kind]; // tile fixed-format board periodically to extend it
     if(textureW[kind] < W*squareSize)
        *x0 = (textureW[kind] - squareSize) * nx/(W-1);
     else