add improved btGeneric6DofSpring2Constraint, thanks to Puhr Gabor and Tamas Umenhoffer!

improved the new demo testbed (work-in-progress)
add basic Lua demo, import URDF test, STL import, obj import

Demos3/AllBullet2Demos/GraphingTexture.h

@@ -0,0 +1,36 @@
+#ifndef GRAPHING_TEXTURE_H
+#define GRAPHING_TEXTURE_H
+#include "LinearMath/btAlignedObjectArray.h"
+
+struct GraphingTexture
+{
+	int m_textureId;
+	//assume rgba (8 bit per component, total of 32bit per pixel, for m_width*m_height pixels)
+	btAlignedObjectArray<unsigned char> m_imageData;
+	int m_width;
+	int m_height;
+	
+	GraphingTexture();
+	virtual ~GraphingTexture();
+	
+	bool create(int texWidth, int texHeight);
+	bool destroy();
+	
+	void setPixel(int x, int y, unsigned char red, unsigned char green, unsigned char blue, unsigned char alpha)
+	{
+		m_imageData[x*4+y*4*m_width+0] = red;
+		m_imageData[x*4+y*4*m_width+1] = green;
+		m_imageData[x*4+y*4*m_width+2] = blue;
+		m_imageData[x*4+y*4*m_width+3] = alpha;
+	}
+	
+	void uploadImageData();
+	
+	int getTextureId()
+	{
+		return m_textureId;
+	}
+};
+
+#endif //GRAPHING_TEXTURE_H
+