48 lines
1.3 KiB
C++
48 lines
1.3 KiB
C++
/**
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* PANDA 3D SOFTWARE
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* Copyright (c) Carnegie Mellon University. All rights reserved.
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*
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* All use of this software is subject to the terms of the revised BSD
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* license. You should have received a copy of this license along
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* with this source code in a file named "LICENSE."
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*
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* @file glLatencyQueryContext_src.cxx
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* @author rdb
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* @date 2014-09-24
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*/
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#ifndef OPENGLES // Timer queries not supported by OpenGL ES.
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TypeHandle CLP(LatencyQueryContext)::_type_handle;
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/**
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*
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*/
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CLP(LatencyQueryContext)::
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CLP(LatencyQueryContext)(CLP(GraphicsStateGuardian) *glgsg,
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int pstats_index) :
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CLP(TimerQueryContext)(glgsg, pstats_index),
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_timestamp(0)
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{
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glgsg->_glGetInteger64v(GL_TIMESTAMP, &_timestamp);
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}
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/**
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* Returns the timestamp that is the result of this timer query. There's no
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* guarantee about which clock this uses, the only guarantee is that
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* subtracting a start time from an end time should yield a time in seconds.
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* If is_answer_ready() did not return true, this function may block before it
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* returns.
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*
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* It is only valid to call this from the draw thread.
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*/
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double CLP(LatencyQueryContext)::
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get_timestamp() const {
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GLint64 time_ns;
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_glgsg->_glGetQueryObjecti64v(_index, GL_QUERY_RESULT, &time_ns);
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return (time_ns - _timestamp) * 0.000000001;
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}
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#endif // OPENGLES
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