36 lines
967 B
Markdown
36 lines
967 B
Markdown
[-] Draw rotated pixels in src order -> cache write miss
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[X] Use atan2 at beginning and end of line.
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Interpolation in-between values
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[X] Test pixel perfect 0, 90
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[X] Optimization for square images
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[X] Fixed point computation
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[-] -funroll-loops -> no gain
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[-] restrict qualifier -> unavailable in C++
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# Cache
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[-] Rotate per channel -> no gain
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[X] Cut image in tiles
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[X] Overlap
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[-] Rotate in one temp tile then copy/move it
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[X] Align tiles in memory
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[ ] Touch beginning of tile
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## Alignement
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[X] RGBX format (create pixel structure) on 8 bytes (can do computation in-place)
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[X] Load pixels in 64-bit variable
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[X] Directly load in SIMD 128-bit variable
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[ ] Align memory on 16 bytes (would require padding)
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[X] RGBX tiles
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## Layout
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[ ] Pack 4 neighbors in 16B structure (aligned)
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Each point is followed by the point below
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[ ] Spiral layout?
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# Quality
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[X] Interpolate using SIMD, SSE
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[ ] Fix out-of-bounds pixel set
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[X] Use padding
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[ ] Image borders
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