fysxasteroids/engine/Sprite.h

#ifndef SPRITE_H
#define SPRITE_H

#include <cmath>
#include <boost/shared_ptr.hpp>

namespace Engine {

/** \brief A simple sprite class that allows animations and multiple sprites in one image
 *
 * Sprites are drawn aligned with the XZ-plane and the Y-axis pointing up.
 *
 */
class Sprite {
	public:
		Sprite() :
			mScale (1.f),
			mWidth (0),
			mHeight (0),
			mGLTextureName (0),
			mSubSpriteCount (1),
			mAnimation (false),
			mAnimationFrameCount(1),
			mAnimationTimer(0.f),
			mAnimationFrameRate(0.f)
		{ }
		Sprite (const Sprite &othersprite) :
			mScale (othersprite.mScale),
			mWidth (othersprite.mWidth),
			mHeight (othersprite.mHeight),
			mGLTextureName (othersprite.mGLTextureName),
			mSubSpriteCount (othersprite.mSubSpriteCount),
			mAnimation (othersprite.mAnimation),
			mAnimationFrameCount(othersprite.mAnimationFrameCount),
			mAnimationTimer(othersprite.mAnimationTimer),
			mAnimationFrameRate(othersprite.mAnimationFrameRate)
			{}
		Sprite& operator= (const Sprite &othersprite) {
			if (this != &othersprite) {
				mScale = othersprite.mScale;
				mWidth = othersprite.mWidth;
				mHeight = othersprite.mHeight;
				mGLTextureName = othersprite.mGLTextureName;
				mSubSpriteCount = othersprite.mSubSpriteCount;
				mAnimation = othersprite.mAnimation;
				mAnimationFrameCount= othersprite.mAnimationFrameCount;
				mAnimationTimer= othersprite.mAnimationTimer;
				mAnimationFrameRate= othersprite.mAnimationFrameRate;
			}

			return *this;
		}

		/** \brief Loads a Sprite from a .png file */
		bool LoadFromPNG (const std::string &filename);
		/** \brief Draws a sprite with the center at the given position */
		void DrawAt (float xpos, float ypos, float zpos);
		void DrawAt2D (float xpos, float ypos);
		unsigned int GetWidth() { return mWidth; };
		unsigned int GetHeight() { return mHeight; };

		void SetSize (unsigned int width, unsigned int height) {
			mWidth = width;
			mHeight = height;
		}
		void SetScale (float scale) { mScale = scale; };

		/** \brief Marks the sprite as an animation and initializes its animation values */
		void SetAnimation (int frame_count, float frame_rate) {
			mAnimation = true;
			mAnimationFrameCount = frame_count;
			mAnimationFrameRate = frame_rate;
			mAnimationTimer = 0.;
			mWidth = static_cast<unsigned int>(ceil (static_cast<float> (mWidth / mAnimationFrameCount)));
		}
		void ResetAnimation () {
			mAnimationTimer = 0.;
		}
		void UpdateAnimation (float seconds) {
			mAnimationTimer += seconds;
			while (mAnimationTimer >= mAnimationFrameCount / mAnimationFrameRate) {
				mAnimationTimer -= mAnimationFrameCount / mAnimationFrameRate;
			}
		}

		void SetGLTextureName (GLuint texture_name) {
			mGLTextureName = texture_name;
		}
		GLuint GetGLTextureName () {
			return mGLTextureName;
		}

		/** \brief Marks the Sprite as a collection of sprites
		 *
		 * All sprites have to be aligned in a row and the SubSprite
		 * functionality eases retrieval and drawing of individual sprites
		 */
		void SetSubSpriteCount (const unsigned int count) {
			mSubSpriteCount = count;
			mWidth = static_cast<unsigned int>(ceil (static_cast<float> (mWidth / mSubSpriteCount)));
		}
		unsigned int GetSubSpriteCount () const {
			return mSubSpriteCount;
		}
		void DrawSubAt (unsigned int index, float xpos, float ypos, float zpos);

	private:
		float mScale;

		unsigned int mWidth;
		unsigned int mHeight;
		GLuint mGLTextureName;

		unsigned int mSubSpriteCount;

		bool mAnimation;
		int mAnimationFrameCount;
		float mAnimationTimer;
		float mAnimationFrameRate;
};

typedef boost::shared_ptr<Sprite> SpritePtr;

}

#endif /* SPRITE_H */