+
+/*******************************************************************************
+
+ Copyright (c) 2009, Charles McGarvey
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*******************************************************************************/
+
+#ifndef _TILEMAP_HH_
+#define _TILEMAP_HH_
+
+/**
+ * @file tilemap.hh
+ * Small subclass to give some basic tile-mapping functionality to textures.
+ */
+
+#include <cassert>
+
+#include <boost/shared_ptr.hpp>
+
+#include "opengl.hh"
+#include "texture.hh"
+
+
+namespace dc {
+
+
+namespace tile {
+
+/**
+ * Possible orientations for texture coordinates.
+ */
+
+typedef enum
+{
+ normal = 0, ///< Normal orientation.
+ flip = 1, ///< Flip over a horizontal axis.
+ reverse = 2, ///< Flip over a vertical axis.
+ flip_and_reverse = 3 ///< Flip over both.
+} orientation;
+
+} // namespace tile
+
+
+/**
+ * A tilemap is a texture which is meant to be divided into smaller sprites.
+ * This class provides all the functionality of a texture and adds some methods
+ * to get texture coordinates to individual tiles within the tilemap. For
+ * simplicity, this class assumes square tiles.
+ */
+
+class tilemap : public texture
+{
+public:
+ tilemap(const std::string& filePath, bool keepInMemory = false,
+ unsigned tilesU = 1, unsigned tilesV = 1)
+ : texture(filePath, keepInMemory), tilesU_(tilesU), tilesV_(tilesV) {}
+
+
+ /**
+ * Set the number of rows and columns of square tiles.
+ * @param tilesU Columns of tiles.
+ * @param tilesV Rows of tiles.
+ */
+
+ void setTileDimensions(unsigned tilesU, unsigned tilesV)
+ {
+ tilesU_ = tilesU;
+ tilesV_ = tilesV;
+ }
+
+
+ /**
+ * Calculate texture coordinates for a tile at a certain index. Tiles are
+ * indexed start with zero as the to-left tile and moving across, then down.
+ * @param index The tile index.
+ * @param coords An array of floats where the texture coordinates will be
+ * stored after this call. The first coordinate (u,v) will be in the first
+ * two places and so on until all four coordinates are stored, therefore
+ * requiring enough room for an array of eight floats. The winding of the
+ * coordinates is always counter-clockwise (the GL default).
+ */
+
+ void getTileCoords(unsigned index, float coords[8])
+ {
+ assert(index < tilesU_ * tilesV_);
+
+ float w = 1.0 / float(tilesU_);
+ float h = 1.0 / float(tilesV_);
+
+ coords[0] = float(index % tilesU_) * w;
+ coords[1] = (float(tilesV_ - 1) - float(index / tilesU_)) * h;
+ coords[2] = coords[0] + w;
+ coords[3] = coords[1];
+ coords[4] = coords[2];
+ coords[5] = coords[1] + h;
+ coords[6] = coords[0];
+ coords[7] = coords[5];
+ }
+
+ /**
+ * This version let's you specify an orientation that will be reflected in
+ * the texture coordinates. This allows you to easily map a texture
+ * backwards or upside-down.
+ * @param what The orientation; can be flip, reverse, or flip_and_reverse.
+ */
+
+ void getTileCoords(unsigned index, float coords[8], tile::orientation what)
+ {
+ getTileCoords(index, coords);
+
+ if (what & tile::flip)
+ {
+ coords[1] = coords[5];
+ coords[5] = coords[3];
+ coords[3] = coords[7];
+ coords[7] = coords[5];
+ }
+ if (what & tile::reverse)
+ {
+ coords[0] = coords[2];
+ coords[2] = coords[6];
+ coords[4] = coords[6];
+ coords[6] = coords[0];
+ }
+ }
+
+private:
+ unsigned tilesU_;
+ unsigned tilesV_;
+};
+
+
+} // namespace dc
+
+#endif // _TILEMAP_HH_
+
projects / chaz / yoink / commitdiff
