Lecture 9 --- Rendering pipeline, shaders and effects
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First part:
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The rendering pipeline
Effects & shaders overview
XNA, HLSL & Effects
Shader authoring tools
Particle Systems
Second part
 Effect, texturing and particle system example
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Rasterization
 Taking vertex positions from the vertex shader
and transforming them into pixels.
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Transform and shading of geometry
Particles: motion + shading
Intermediate buffers (textures)
Post processing
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Texture
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Texture +
Directional light
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Texture +
Directional light +
Spotlight
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Texture +
Directional light +
Spotlight +
Normal map
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Texture +
Directional light +
Spotlight +
Normal map +
Pointlight
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Texture +
Directional light +
Spotlight +
Normal map +
Pointlight +
Shadows
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Example: Heat texture
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Example: Soft shadows
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Bloom disabled
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C-like syntax
No object orientation
Functions can be used
 By using include-files, functions and datatypes
can be reused
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Vertex shader
 Used to transform vertices
▪ Solids deforming
▪ Skeletal animation
▪ Particle motion
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Pixel shader
 Manipulates pixel color and optionally the pixel
depth.
 Examples:
▪ Lighting
▪ Contrast
▪ Blur
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Easy to work with in XNA
Represented by the class Effect
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Effect effect;
effect.Load<Effect>(”/effects/lightEffect”);
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You can then set the attributes of the effect
 effect.Parameters[”lightPosition”].SetValue()
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To make the code more robust and efficient, implement a
helper class for each effect.
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After a while, you may want to find a faster way of adding
new shaders
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Complete IDE´s available for developing
shaders
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A way to simulate explosions, water, fire etc.
Particles behave in a similar, yet slightly
different way
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Particles created and killed on the CPU
Custom vertex declaration used
Pooling should be used (no memory
allocation during runtime)
Current position/color/size of each particle
calculated in vertex shader
Final color decided in pixel shader
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