Uploaded byMinh Nghiem
Working with Shader with Unity
A shader is a program that runs in the graphics pipeline and tells the computer how to render each pixel. The graphics pipeline consists of six main stages: vertex processing, primitive assembly, primitive processing, rasterization, fragment processing, and per-fragment operations. In vertex processing, vertex shaders transform 3D coordinates, while fragment/pixel shaders color each pixel in the framebuffer during fragment processing. Together, vertex and fragment shaders control lighting, texturing, and other visual effects.
Working with Shader with Unity
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- 2. What is aShader ? A shader is a program that runs in the graphics pipeline in CPU and tells the computer how to render each pixel. These programs are called shaders because they're often used to control lighting and shading, but they also can handle other special effects.
- 3. Minecraft before andafter shader
- 4. Graphic rendering pipeline Consistsof six stages: 1. Per-Vertex Operation 2. Primitive Assembly 3. Primitive Processing 4. Rasterization 5. Fragment Processing
- 5. Per-Vertex Operation Transform fromthe local coordinate system to the 3d world coordinate system. A model of a teapot in abstract is placed in the coordinate system of the 3d world. Vertex shader comes here.
- 6. Per Vertex Operation- Lighting and shading is programmable
- 7. Primitive Assembly Traditionally thisis done using triangles, as a result a primitive is assembled, e.g. a triangle.
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- 9. Primitive Processing Geometric primitivesthat now fall completely outside of the viewing frustum will not be visible and are discarded at this stage.
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- 11. Rasterization Primitives are thenbroken down into smaller units, corresponding to pixels in the framebuffer. Each of these smaller units are called Fragments. Fragment shader comes after here.
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- 13. Fragment Processing Once theprimitive has been rasterized, color/texture is applied to the geometry.
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- 15. Per-Fragment Operation Fragments aresubmitted to tests: 1. Pixel Ownership - not customizable by applications 2. Scissor - fails if fragment is outside of a specified rectangle 3. Alpha - outcome depends on alpha of the fragment 4. Stencil - outcome depends on value in stencil buffer 5. Depth - outcome depends on depth of fragment 6. Blending - outcome depends on fragment color 7. Dithering - not customizable by applications 8. Logical operations - outcome depends on color of fragment
- 16. Per-Fragment Operation -usually configurable but not programmable
- 17. The ultimate goalof the Vertex Shader is to provide the final transformation of the mesh vertices to the rendering pipeline. Vertex Shader
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- 19. The goal ofthe Fragment shader is to provide Coloring and Texture data to each pixel heading to the framebuffer. A framebuffer is a bitmap that is used to refresh a display from a memory buffer containing a complete frame of data. Fragment/Pixel Shader
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- 21. MSAA - eachpixel at the edge of a polygon is sampled multiple times. For each sample-pass, a slight offset is applied to all screen coordinates.