Simple Shadow Mapping

It's been a while since my last blog post, but I've not just been sat on my arse doing nothing. Well I did go to cyrpus for a week so that is a bit of a lie. Since getting back I have been working on Shadow Mapping which has taken me a fair few hours. First getting the theory of it down and then diving in and trying to implement it. This failed pretty quickly and I decided to break it down into much smaller parts. First I created a second framebuffer to use to render the depth map. To check that this framebuffer was working correctly I created a Render Method that did a straight copy from one texture to the screen. This also gave me the chance to output the depth map to ensure that it was being created properly. 

The second part was creating the shader that would calculate whether the pixel was in shadow or not. This part was a little difficult as I was using various sources of information for this and they all did things slightly differently. The most difficult was ensuring that the texture co-ordinates were being calculated correctly. Which meant I had to pass in the Lights View Projection Matrix. My confusion came mostly whether It needed to include the lights model matrix or not, or the actual model matrix for the object. After a lot of shader debugging I managed to get it all Working and here it is: 

As you can see the shadow maps are pretty solid and it still needs a little work. Luckily I decided early on to use the Colour Buffer for rendering the depth which means I can now easily port this to use Variance Shadow Maps. This will allow for a more gradual fade from shadow to light.

As I have implemented the render method for a full screen texture and a new framebuffer, it now means I will easily be able to add post processing effects into my project. by bouncing from the default frame buffer to my newly created one and back until finally displaying the final image on screen using the full screen texture render method.

All of which I am hoping are things to come.