HTML Injection Attacks: Impact and Mitigation Strategies
Accelerometer and Open GL
1. Introduction to Accelerometers and
OpenGL ES on the iPhone
Jon Liang
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Mobility Lead – Mobclix
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http://www.mobclix.com
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Jeff LaMarche
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Author - Beginning iPhone Development: Exploring
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the iPhone SDK
http://iphonedevelopment.blogspot.com/
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8. Quartz 2D vs. OpenGL for 2D
Quartz 2D
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Higher Level API
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Compatible with
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CoreAnimation
Easier to Display Text
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Inverted y-axis
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OpenGL
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Low Level API
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More Control
– Source: Apple
Less Overhead
–
3D
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9. iPhone Limitations
24 MB of Memory for textures and surfaces.
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The maximum texture size is 1024 x 1024.
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2D texture targets are supported; other texture
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targets are not.
Stencil buffers aren’t available.
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More Info:
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http://developer.apple.com/iphone/library/documentation/i
–
Phone/Conceptual/iPhoneOSProgrammingGuide/Graphi
csandDrawing/chapter_6_section_5.html#//apple_ref/doc
/uid/TP40007072-CH10-SW18
10. Open GL → OpenGL ES
Removed glBegin() and glEnd()
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Use glDrawArrays() or glDrawElements()
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Added Fixed Point data types
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Embedded systems often don't have FPU's.
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Removed convenience functions
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More lightweight implementation.
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13. Accelerometer
Hardware
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3-Axis MEMS Accelerometer
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Part Number: LIS302DL
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Max Sample Rate: 400 Hz
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Max Acceleration: ± 8g
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No Gyroscope
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Implications
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No Direct Angular Acceleration Data
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Zeroed at Free Fall
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Limited Amplitude (± 4g per axis)
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14. Basic Tasks: Signal Processing
Isolating Large Movements
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Low-Pass Filter:
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xn = xn-1/2 + x/2
Isolating Small Movements
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High-Pass Filter:
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xn = x - xn-1
Sournce: http://jp.physoc.org/content/vol550/issue3/fulltext/873/Figures/HiRes/873-F2.gif