1 files changed, 120 insertions, 0 deletions
diff --git a/src/sugar/sugar-grid.c b/src/sugar/sugar-grid.c
new file mode 100644
index 0000000..3fa7de5
--- /dev/null
+++ b/src/sugar/sugar-grid.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2008, Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "sugar-grid.h"
+
+static void sugar_grid_class_init (SugarGridClass *grid_class);
+static void sugar_grid_init       (SugarGrid *grid);
+
+
+G_DEFINE_TYPE(SugarGrid, sugar_grid, G_TYPE_OBJECT)
+
+void
+sugar_grid_setup(SugarGrid *grid, gint width, gint height)
+{
+    g_free(grid->weights);
+
+    grid->weights = g_new0(guchar, width * height);
+    grid->width = width;
+    grid->height = height;
+}
+
+static gboolean
+check_bounds(SugarGrid *grid, GdkRectangle *rect)
+{
+    return (grid->weights != NULL &&
+            grid->width >= rect->x + rect->width &&
+            grid->height >= rect->y + rect->height);
+}
+
+void
+sugar_grid_add_weight(SugarGrid *grid, GdkRectangle *rect)
+{
+    int i, k;
+
+    if (!check_bounds(grid, rect)) {
+        g_warning("Trying to add weight outside the grid bounds.");
+        return;
+    }
+
+    for (k = rect->y; k < rect->y + rect->height; k++) {
+        for (i = rect->x; i < rect->x + rect->width; i++) {
+            grid->weights[i + k * grid->width] += 1;
+        }
+    }
+}
+
+void
+sugar_grid_remove_weight(SugarGrid *grid, GdkRectangle *rect)
+{
+    int i, k;
+
+    if (!check_bounds(grid, rect)) {
+        g_warning("Trying to remove weight outside the grid bounds.");
+        return;
+    }
+
+    for (k = rect->y; k < rect->y + rect->height; k++) {
+        for (i = rect->x; i < rect->x + rect->width; i++) {
+            grid->weights[i + k * grid->width] -= 1;
+        }
+    }
+}
+
+guint
+sugar_grid_compute_weight(SugarGrid *grid, GdkRectangle *rect)
+{
+    int i, k, sum = 0;
+
+    if (!check_bounds(grid, rect)) {
+        g_warning("Trying to compute weight outside the grid bounds.");
+        return 0;
+    }
+
+    for (k = rect->y; k < rect->y + rect->height; k++) {
+        for (i = rect->x; i < rect->x + rect->width; i++) {
+            sum += grid->weights[i + k * grid->width];
+        }
+    }
+
+    return sum;
+}
+
+static void
+sugar_grid_finalize(GObject *object)
+{
+    SugarGrid *grid = SUGAR_GRID(object);
+
+    g_free(grid->weights);
+}
+
+static void
+sugar_grid_class_init(SugarGridClass *grid_class)
+{
+    GObjectClass *gobject_class;
+
+    gobject_class = G_OBJECT_CLASS(grid_class);
+    gobject_class->finalize = sugar_grid_finalize;
+}
+
+static void
+sugar_grid_init(SugarGrid *grid)
+{
+    grid->weights = NULL;
+}