The formula is at the bottom of the page:. In the following function, SetupOrtho int cx, int cy , values for the real world origin and maximum coordinate values are used to set up the clip rectangle. Now lets take a look at the changes made to the GraphicsClass: Graphicsclass. We need to release the DepthStencilView and ShaderResourceView that we created in order to avoid leaking memory. Remember, directional lights are assumed to be infinitely far away, so all light rays originating from the light are considered parallel, and so the shadow cast by an object should be the same size as the object, that is, the volume that is in shadow is shaped like a rectangular prism.
We will also add calls to BeginScene and EndScene in the Render function so that we are now drawing to the window using Direct3D. Some machines may have the primary card as a DirectX 10 video card and the secondary card as a DirectX 11 video card. . For a quick look at loading shader resources see. The major difference in this tutorial is that ModelClass has been replaced with BitmapClass and that we are using the TextureShaderClass again instead of the LightShaderClass. Once we have picking in place, we will be able to select areas on our terrain, which will be very important going forward, when we move on to moving units around and implementing pathfinding.
This check can save us a lot of processing. Note that we need to compute a bounding sphere for the entirety of our scene geometry; in this case, we know how the scene is laid out, and so can construct this sphere easily in the constructor. If vsync is set to true in our graphicsclass. It has the regular constructor, copy constructor, and destructor. However if we set vsync to false then it will draw the screen as many times a second as it can, however this can cause some visual artifacts.
For DirectX the middle of the screen is 0,0. For both cases, we define the ray to be: Assuming nothing, we need to calculate. You can change this size to whatever you like as it does not need to reflect the exact size of the texture. The UpdateBuffers function is called with the position parameters. The relevant project is the Minimap project. We will use the device and device context for almost everything from this point forward.
Most shaders will need these matrices for rendering so there needed to be an easy way for outside objects to get a copy of them. If you can find a copy it appears to be out of print, and copies are going for outrageous prices on Amazon… , I would highly recommend grabbing it. For 2D images we just need a position vector and texture coordinates. This will bind the render target view and the depth stencil buffer to the output render pipeline. These buffers are much slower than static vertex buffers but that is the trade off for the extra functionality.
These can be checked with and. These will be required for generating exact vertex locations during rendering. All of this functionality will be wrapped up into a class, so that we can render multiple minimaps, and place them wherever we like within our application window. In our example, the direction of the shadow-casting light changes over time, to highlight how the shadows change. Creating the orthographic projection matrix in our SetLens function will be performed a little differently than the base function in CameraBase. However before doing that I put in a call to force the swap chain to go into windowed mode first before releasing any pointers.
This opens the door for rendering user interfaces and font systems. What would be the motivation to do this in shaders? I hope it can be of use to anyone. Calculating the position from the z-value: Generalization In the perspective-only case, we reconstructed the position value assuming the ray origin was 0. We send this function the screen width, screen height, handle to the window, and the four global variables from the Graphicsclass. Finally, we can use the normal Terrain Draw function to render the terrain, using our OrthoCamera instead of the main view camera. This is not the case with an orthogonal projection - moving the camera will not change the size of rendered objects, it will only change what is visible i. Thus, we will be running the BuildShadowTransform function each frame, as part of our UpdateScene method.
The first thing we'll do is fill out the description of the swap chain. Once you are done drawing 2D graphics re-enable the Z buffer again so you can render 3D objects properly again. Please pardon the possible stupid questions to follow! Change the clear color in GraphicsClass::Render to yellow. ShutdownBuffers ; return; } Render puts the buffers of the 2D image on the video card. Description, 128 ; if error! The article encouraged me to go back and revisit the mathematics of projection.
The full source for this example can be downloaded from my GitHub repository at , under the ShadowDemos project. In other words, they can just be passed on as they are. Note that I check to see if the pointer was initialized or not. Results In the screenshots shown, we are also drawing the shadow map depth texture to a quad in the lower right-hand corner of the window, just to visualize what the depth buffer looks like and check our results. Direct3D will need this handle to access the window previously created.