add HexTile class

src/client/Client.cc

@@ -243,6 +243,8 @@ void Client::draw_map()
     for (int y = 0; y < height; y++)
     {
         for (int x = 0; x < width; x++)
+        {
+            if (m_map.tile_present(x, y))
             {
                 glPushMatrix();
                 glTranslatef(span_x * x, span_y * y, 0);
@@ -265,6 +267,7 @@ void Client::draw_map()
                 glPopMatrix();
             }
         }
+    }
     glPopMatrix();
     glPopAttrib();
 }

src/common/HexTile.cc

@@ -0,0 +1,51 @@
+
+#include "HexTile.h"
+
+#define COS_60 0.5
+#define SIN_60 0.8660254037844386
+
+/* points of a horizontal hexagon 2.0 units high */
+static const float hex_points[][2] = {
+    {1.1547005383792517, 0.0},
+    {0.577350269189626, 1.0},
+    {-0.5773502691896256, 1.0},
+    {-1.1547005383792517, 0.0},
+    {-0.5773502691896264, -1.0},
+    {0.577350269189626, -1.0}
+};
+
+HexTile::HexTile(float x, float y, float size)
+{
+    m_x = x;
+    m_y = y;
+    m_size = size;
+}
+
+bool HexTile::point_within(float x, float y)
+{
+    x = 2.0 * (x - m_x) / m_size;
+    y = 2.0 * (y - m_y) / m_size;
+    /* a point (x, y) at angle q rotates to (x', y') by f deg around the origin
+     * according to:
+     *  x' = r*cos(q+f) = r*cos(q)*cos(f)-r*sin(q)*sin(f)
+     *  y' = r*sin(q+f) = r*sin(q)*cos(f)+r*cos(q)*sin(f)
+     *  x' = x*cos(f) - y*sin(f)
+     *  y' = y*cos(f) + x*sin(f)
+     * cos(60 deg) = 0.5
+     * sin(60 deg) = 0.8660254
+     * so:
+     *  x' = x * 0.5 - y * 0.8660254
+     *  y' = y * 0.5 + x * 0.8660254
+     */
+    if ((y > 1.0) || (y < -1.0))
+        return false;
+    float rx = x * COS_60 - y * SIN_60;
+    float ry = y * COS_60 + x * SIN_60;
+    if ((ry > 1.0) || (ry < -1.0))
+        return false;
+    x = rx * COS_60 - ry * SIN_60;
+    y = ry * COS_60 + rx * SIN_60;
+    if ((y > 1.0) || (y < -1.0))
+        return false;
+    return true;
+}

src/common/HexTile.h

@@ -0,0 +1,16 @@
+
+#ifndef HEXTILE_H
+#define HEXTILE_H
+
+class HexTile
+{
+    public:
+        HexTile(float x, float y, float size);
+        bool point_within(float x, float y);
+    protected:
+        float m_x;
+        float m_y;
+        float m_size;
+};
+
+#endif

src/common/Map.cc

@@ -1,5 +1,6 @@
 
 #include "Map.h"
+#include "HexTile.h"
 
 using namespace std;
 
@@ -7,7 +8,13 @@ Map::Map(int width, int height)
 {
     m_width = width;
     m_height = height;
-    m_grid = vector< vector< bool > >(height, vector<bool>(width, true));
+    m_grid = vector< vector< bool > >(height, vector<bool>(width));
+
+    /* construction of default map - temporary */
+    HexTile ht(width / 2.0, height / 2.0, 0.8 * height / 2.0);
+    for (int i = 0; i < height; i++)
+        for (int j = 0; j < width; j++)
+            m_grid[i][j] = ht.point_within(j + 0.5, i + 0.5);
 }
 
 bool Map::tile_present(int x, int y)