I'm trying to draw textures aligned with this physics body whose coordinate system's origin is at the center of the screen. (XNA)Spritebatch has its default origin set to top-left corner. I got the textures to be positioned correctly, but I noticed my textures are vertically inverted. That is, an arrow texture pointing Up , when rendered points down. I'm not sure where I am going wrong with the math.

My approach is to convert everything in physic's meter units and draw accordingly.

        Matrix proj = Matrix.CreateOrthographic(scale * graphics.GraphicsDevice.Viewport.AspectRatio, scale, 0, 1);
        Matrix view = Matrix.Identity;

        effect.World = Matrix.Identity;
        effect.View = view;
        effect.Projection = proj;

        effect.TextureEnabled = true;
        effect.VertexColorEnabled = true;

        effect.Techniques[0].Passes[0].Apply();
        SpriteBatch.Begin(SpriteSortMode.BackToFront, BlendState.AlphaBlend, null, DepthStencilState.Default, RasterizerState.CullNone, effect);

        m_Paddles[1].Draw(gameTime);

        SpriteBatch.End();

where Paddle::Draw looks like:

       SpriteBatch.Draw(paddleTexture,
            mBody.Position,
            null,
            Color.White,
            0f,
            new Vector2(16f, 16f),  // origin of the texture
            0.1875f, SpriteEffects.None,   // width of box is 3*2 = 6 meters. texture is 32 pixels wide. to make it 6 meters wide in world space: 6/32 = 0.1875f
            0);

The orthographic projection matrix seem fine to me, but I am obviously doing something wrong somewhere! Can someone please help me figure out what am i doing wrong here ?

Thanks