Created Graphics API (markdown)

Graphics-API.md

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+IGraphicsAPI (accessed usually via game.Graphics) is a simplistic low level abstraction of 3D graphics hardware. 
+
+**There are no fancy shaders, objects, framebuffers, etc.**
+
+Built-in implementations of IGraphicsAPI include Direct3D 9, OpenGL (1.5, or 1.2 with ARB_vertex_buffer_object), and OpenGL ES 1.1. 
+
+
+***
+### Textures
+**Note**: The only supported bitmap formats are 32 bits per pixel, with power of two dimensions.
+
+**`MaxTextureDimensions`** - Gets the maximum supported dimension size (i.e. width and height) for a texture.
+
+**`Texturing`** - Sets whether texturing is used when drawing/rasterizing. **It is extremely important that you enable this before drawing textured vertices, and disable it afterwards.**
+
+**`CreateTexture(source)`** - Creates a new native texture from a Bitmap or FastBitmap object, returning its id. This id is used in all other texture related methods.
+
+**`BindTexture(id)`** - Sets the active texture used for drawing/rasterization.  
+
+**`DeleteTexture(id)`** - Deletes the native texture with that id, and resets id to -1.
+
+**`UpdateTexturePart(id, x, y, part)`** - Fills the region (x, y, part.Width, part.Height) in the native texture with that id, with the pixels from part.
+_Note on OpenGL backends, this also changes the active texture to id._
+***
+### Vertices
+**Note**: The only supported formats are (XYZ float32, ARGB uint8) and (XYZ float32, ARGB uint8, UV float32).
+
+**Note**: The actual order of ARGB components differs depending on the underlying implementation, use FastColour.Pack() to pack a colour into the correct order.
+
+**Note**: The only supported drawing modes are triangles, lines, and indexed triangles (i.e. quads).