From 4dd02dac2fcaf45f398c074735a7359330f78d77 Mon Sep 17 00:00:00 2001
From: Marcus Müller <mmueller@gnuradio.org>
Date: Thu, 25 Mar 2021 18:13:35 +0100
Subject: analog/fastnoise: avoid modulo operation when picking indices
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
When the pool is power-of-2-sized, index generation can be done using a simple bitmask. Document this, add logging info.
- use unsigned and fixed-length int where due
- avoid expensive integer modulo operation when possible
- extract power-of-two constexpr
- don't clutter the logs for small pool sizes
Signed-off-by: Marcus Müller <marcus@hostalia.de>
---
gr-analog/include/gnuradio/analog/fastnoise_source.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
(limited to 'gr-analog/include/gnuradio/analog/fastnoise_source.h')
diff --git a/gr-analog/include/gnuradio/analog/fastnoise_source.h b/gr-analog/include/gnuradio/analog/fastnoise_source.h
index 8edc8d972d..e03bdff08e 100644
--- a/gr-analog/include/gnuradio/analog/fastnoise_source.h
+++ b/gr-analog/include/gnuradio/analog/fastnoise_source.h
@@ -46,10 +46,11 @@ public:
* \param seed seed for random generators. Note that for uniform
* and Gaussian distributions, this should be a negative
* number.
- * \param samples Number of samples to pre-generate
+ * \param samples Number of samples to pre-generate. For performance
+ * reasons, prefer a power of 2.
*/
static sptr
- make(noise_type_t type, float ampl, long seed = 0, long samples = 1024 * 16);
+ make(noise_type_t type, float ampl, uint64_t seed = 0, size_t samples = 1024 * 16);
virtual T sample() = 0;
virtual T sample_unbiased() = 0;
virtual const std::vector<T>& samples() const = 0;
--
cgit v1.2.3