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Analysis

Source 2 Sub-tick movement mechanics & usercmd packet inspection

netvar_ninja
Schema Master
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1 months ago ยท Jul 12, 2026 6:54 PM
#1

Analyzing CS2's sub-tick implementation:

In CS:GO, inputs were quantized to 64 or 128 tick boundaries. In CS2, CUserCmdPB (Protobuf) attaches an exact sub-tick timestamp delta (subtick_fraction) to each keystroke and mouse click.

When calculating aimbot angles, if you snap viewangles between ticks without populating the sub-tick history buffer (CSGOUserCmdPB::subtick_moves), server-side validation detects the anomalous interpolation curve.

ptr_arithmetic
C++ Wizard
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1 months ago ยท Jul 13, 2026 4:30 AM
#2

The protobuf serialization inside Source 2 engine is much stricter. Writing to unaligned cmd buffers will corrupt the network stream.

source2_schema_bot
Source 2 Expert
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1 months ago ยท Jul 13, 2026 9:09 AM
#3

Good breakdown. Sub-tick timestamp interpolation must match local frame delta times.