ipa: rpi: Replace last users of math.h

As described in the coding style document, libcamera favours <cmath>
over <math.h>. Replace the last few occurrences of the latter with the
former in the Raspberry Pi IPA and adapt the code accordingly. In some
cases, the <math.h> include is simply dropped as it isn't needed.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>

src/ipa/rpi/cam_helper/cam_helper_imx283.cpp

@@ -8,7 +8,7 @@
 #include <assert.h>
 
 #include "cam_helper.h"
-#include "math.h"
+
 using namespace RPiController;
 
 class CamHelperImx283 : public CamHelper

src/ipa/rpi/cam_helper/cam_helper_imx290.cpp

@@ -5,7 +5,7 @@
  * camera helper for imx290 sensor
  */
 
-#include <math.h>
+#include <cmath>
 
 #include "cam_helper.h"
 
@@ -37,13 +37,13 @@ CamHelperImx290::CamHelperImx290()
 
 uint32_t CamHelperImx290::gainCode(double gain) const
 {
-	int code = 66.6667 * log10(gain);
+	int code = 66.6667 * std::log10(gain);
 	return std::max(0, std::min(code, 0xf0));
 }
 
 double CamHelperImx290::gain(uint32_t gainCode) const
 {
-	return pow(10, 0.015 * gainCode);
+	return std::pow(10, 0.015 * gainCode);
 }
 
 void CamHelperImx290::getDelays(int &exposureDelay, int &gainDelay,

src/ipa/rpi/controller/histogram.cpp

@@ -4,7 +4,7 @@
  *
  * histogram calculations
  */
-#include <math.h>
+#include <cmath>
 #include <stdio.h>
 
 #include "histogram.h"
@@ -49,9 +49,9 @@ double Histogram::interBinMean(double binLo, double binHi) const
 {
 	assert(binHi >= binLo);
 	double sumBinFreq = 0, cumulFreq = 0;
-	for (double binNext = floor(binLo) + 1.0; binNext <= ceil(binHi);
+	for (double binNext = std::floor(binLo) + 1.0; binNext <= std::ceil(binHi);
 	     binLo = binNext, binNext += 1.0) {
-		int bin = floor(binLo);
+		int bin = std::floor(binLo);
 		double freq = (cumulative_[bin + 1] - cumulative_[bin]) *
 			      (std::min(binNext, binHi) - binLo);
 		sumBinFreq += bin * freq;

src/ipa/rpi/controller/rpi/af.cpp

@@ -7,8 +7,8 @@
 
 #include "af.h"
 
+#include <cmath>
 #include <iomanip>
-#include <math.h>
 #include <stdlib.h>
 
 #include <libcamera/base/log.h>

src/ipa/rpi/controller/rpi/black_level.cpp

@@ -5,7 +5,6 @@
  * black level control algorithm
  */
 
-#include <math.h>
 #include <stdint.h>
 
 #include <libcamera/base/log.h>

src/ipa/rpi/controller/rpi/lux.cpp

@@ -4,7 +4,6 @@
  *
  * Lux control algorithm
  */
-#include <math.h>
 
 #include <libcamera/base/log.h>
 

src/ipa/rpi/controller/rpi/noise.cpp

@@ -5,7 +5,7 @@
  * Noise control algorithm
  */
 
-#include <math.h>
+#include <cmath>
 
 #include <libcamera/base/log.h>
 
@@ -69,7 +69,7 @@ void Noise::prepare(Metadata *imageMetadata)
 		 * make some adjustments based on the camera mode (such as
 		 * binning), if we knew how to discover it...
 		 */
-		double factor = sqrt(deviceStatus.analogueGain) / modeFactor_;
+		double factor = std::sqrt(deviceStatus.analogueGain) / modeFactor_;
 		struct NoiseStatus status;
 		status.noiseConstant = referenceConstant_ * factor;
 		status.noiseSlope = referenceSlope_ * factor;

src/ipa/rpi/controller/rpi/sharpen.cpp

@@ -5,7 +5,7 @@
  * sharpening control algorithm
  */
 
-#include <math.h>
+#include <cmath>
 
 #include <libcamera/base/log.h>
 
@@ -68,7 +68,7 @@ void Sharpen::prepare(Metadata *imageMetadata)
 	 * we adjust the limit and threshold less aggressively. Using a sqrt
 	 * function is an arbitrary but gentle way of accomplishing this.
 	 */
-	double userStrengthSqrt = sqrt(userStrength_);
+	double userStrengthSqrt = std::sqrt(userStrength_);
 	struct SharpenStatus status;
 	/*
 	 * Binned modes seem to need the sharpening toned down with this