Game Engine II Assignment03

Download Link

GIF of MyGame

How I made Graphics.cpp platform-independent

I created a cView class and implemented some interfaces such as: ClearBuffers, InitializeViews and CleanUp. Then I implemented these functions in cView.d3d.cpp and cView.gl.cpp.

I also created an interface called SwapBuffer in sContext class for different platform to swap content from back buffer to front buffer. Then I implemented it in sContext.d3d.cpp and sContext.gl.cpp.

Then for the content that is the same in d3d and gl platform, I just move them into Graphics.cpp.

The code that clears the back buffer color

I used the s_view_ClearBuffers(0.0f, 0.0f, 0.0f) to clear the back buffer color. Then I changed the parameters to rgb values to make animated color for the background.

The screenshot of my game with a different background color

The code that initializes an effect

I used Vertex Shader Path and Fragment Shader Path as parameters to initialize an effect.

Memory a single effect takes up in both platforms

x64: 48
x86: 16

The code that initializes a mesh

I used TriangleCount, VertexCountPerTriangle and VertexData as parameters to initialize a mesh.

Memory a single mesh takes up in both platforms

x64: 24
x86: 12

The size differences between platforms arise from:

Pointer Size Variation:
- On different platforms (32-bit vs. 64-bit), pointers have different sizes (4 bytes vs. 8 bytes).
Platform-Specific Data Structures:
- Different platforms use different types for handling resources (e.g., pointers vs. IDs), leading to variations in data representation and storage.
Additional Platform-Specific Data:
- Additional platform-specific members (like m_vertexArrayId in OpenGL) increase the memory footprint.

These variations are necessary to interface correctly with the different graphics APIs (Direct3D vs. OpenGL) and cannot be uniformly minimized without compromising functionality or compatibility.