Backport Night Color feature to X11

Summary:
The color correction manager doesn't make any specific assumptions about
underlying platform, e.g. whether it's x11, etc. The platform just
has to be capable of setting gamma ramps. Given that, there are no any
significant technical blockers for making this feature work on x.

Reviewers: #kwin, davidedmundson, romangg

Reviewed By: #kwin, davidedmundson, romangg

Subscribers: romangg, neobrain, GB_2, filipf, davidedmundson, ngraham, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D21345

abstract_output.cpp

@@ -17,16 +17,53 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *********************************************************************/
+
 #include "abstract_output.h"
 
-// KF5
-#include <KLocalizedString>
-
-#include <cmath>
-
 namespace KWin
 {
 
+GammaRamp::GammaRamp(uint32_t size)
+    : m_table(3 * size)
+    , m_size(size)
+{
+}
+
+uint32_t GammaRamp::size() const
+{
+    return m_size;
+}
+
+uint16_t *GammaRamp::red()
+{
+    return m_table.data();
+}
+
+const uint16_t *GammaRamp::red() const
+{
+    return m_table.data();
+}
+
+uint16_t *GammaRamp::green()
+{
+    return m_table.data() + m_size;
+}
+
+const uint16_t *GammaRamp::green() const
+{
+    return m_table.data() + m_size;
+}
+
+uint16_t *GammaRamp::blue()
+{
+    return m_table.data() + 2 * m_size;
+}
+
+const uint16_t *GammaRamp::blue() const
+{
+    return m_table.data() + 2 * m_size;
+}
+
 AbstractOutput::AbstractOutput(QObject *parent)
     : QObject(parent)
 {

abstract_output.h

@@ -25,13 +25,64 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QObject>
 #include <QRect>
 #include <QSize>
+#include <QVector>
 
 namespace KWin
 {
 
-namespace ColorCorrect {
-struct GammaRamp;
-}
+class KWIN_EXPORT GammaRamp
+{
+public:
+    GammaRamp(uint32_t size);
+
+    /**
+     * Returns the size of the gamma ramp.
+     **/
+    uint32_t size() const;
+
+    /**
+     * Returns pointer to the first red component in the gamma ramp.
+     *
+     * The returned pointer can be used for altering the red component
+     * in the gamma ramp.
+     **/
+    uint16_t *red();
+
+    /**
+     * Returns pointer to the first red component in the gamma ramp.
+     **/
+    const uint16_t *red() const;
+
+    /**
+     * Returns pointer to the first green component in the gamma ramp.
+     *
+     * The returned pointer can be used for altering the green component
+     * in the gamma ramp.
+     **/
+    uint16_t *green();
+
+    /**
+     * Returns pointer to the first green component in the gamma ramp.
+     **/
+    const uint16_t *green() const;
+
+    /**
+     * Returns pointer to the first blue component in the gamma ramp.
+     *
+     * The returned pointer can be used for altering the blue component
+     * in the gamma ramp.
+     **/
+    uint16_t *blue();
+
+    /**
+     * Returns pointer to the first blue component in the gamma ramp.
+     **/
+    const uint16_t *blue() const;
+
+private:
+    QVector<uint16_t> m_table;
+    uint32_t m_size;
+};
 
 /**
  * Generic output representation in a Wayland session
@@ -64,10 +115,10 @@ public:
         return Qt::PrimaryOrientation;
     }
 
-    virtual int getGammaRampSize() const {
+    virtual int gammaRampSize() const {
         return 0;
     }
-    virtual bool setGammaRamp(const ColorCorrect::GammaRamp &gamma) {
+    virtual bool setGammaRamp(const GammaRamp &gamma) {
         Q_UNUSED(gamma);
         return false;
     }

colorcorrection/gammaramp.h

@@ -1,53 +0,0 @@
-/********************************************************************
- KWin - the KDE window manager
- This file is part of the KDE project.
-
-Copyright 2017 Roman Gilg <subdiff@gmail.com>
-
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*********************************************************************/
-#ifndef KWIN_GAMMARAMP_H
-#define KWIN_GAMMARAMP_H
-
-namespace KWin
-{
-
-namespace ColorCorrect
-{
-
-struct GammaRamp {
-    GammaRamp(int _size) {
-        size = _size;
-        red = new uint16_t[3 * _size];
-        green = red + _size;
-        blue = green + _size;
-    }
-    ~GammaRamp() {
-        delete[] red;
-        red = green = blue = nullptr;
-    }
-
-    uint32_t size = 0;
-    uint16_t *red = nullptr;
-    uint16_t *green = nullptr;
-    uint16_t *blue = nullptr;
-
-private:
-    Q_DISABLE_COPY(GammaRamp)
-};
-
-}
-}
-
-#endif // KWIN_GAMMARAMP_H

colorcorrection/manager.cpp

@@ -20,7 +20,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "manager.h"
 #include "colorcorrectdbusinterface.h"
 #include "suncalc.h"
-#include "gammaramp.h"
 #include <colorcorrect_logging.h>
 
 #include <main.h>
@@ -513,20 +512,23 @@ void Manager::commitGammaRamps(int temperature)
     const auto outs = kwinApp()->platform()->outputs();
 
     for (auto *o : outs) {
-        int rampsize = o->getGammaRampSize();
+        int rampsize = o->gammaRampSize();
         GammaRamp ramp(rampsize);
 
         /*
          * The gamma calculation below is based on the Redshift app:
          * https://github.com/jonls/redshift
          */
+        uint16_t *red = ramp.red();
+        uint16_t *green = ramp.green();
+        uint16_t *blue = ramp.blue();
 
         // linear default state
         for (int i = 0; i < rampsize; i++) {
                 uint16_t value = (double)i / rampsize * (UINT16_MAX + 1);
-                ramp.red[i] = value;
-                ramp.green[i] = value;
-                ramp.blue[i] = value;
+                red[i] = value;
+                green[i] = value;
+                blue[i] = value;
         }
 
         // approximate white point
@@ -538,9 +540,9 @@ void Manager::commitGammaRamps(int temperature)
         whitePoint[2] = (1. - alpha) * blackbodyColor[bbCIndex + 2] + alpha * blackbodyColor[bbCIndex + 5];
 
         for (int i = 0; i < rampsize; i++) {
-            ramp.red[i] = (double)ramp.red[i] / (UINT16_MAX+1) * whitePoint[0] * (UINT16_MAX+1);
-            ramp.green[i] = (double)ramp.green[i] / (UINT16_MAX+1) * whitePoint[1] * (UINT16_MAX+1);
-            ramp.blue[i] = (double)ramp.blue[i] / (UINT16_MAX+1) * whitePoint[2] * (UINT16_MAX+1);
+            red[i] = qreal(red[i]) / (UINT16_MAX+1) * whitePoint[0] * (UINT16_MAX+1);
+            green[i] = qreal(green[i]) / (UINT16_MAX+1) * whitePoint[1] * (UINT16_MAX+1);
+            blue[i] = qreal(blue[i]) / (UINT16_MAX+1) * whitePoint[2] * (UINT16_MAX+1);
         }
 
         if (o->setGammaRamp(ramp)) {

plugins/platforms/drm/drm_object_crtc.cpp

@@ -23,7 +23,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "drm_buffer.h"
 #include "drm_pointer.h"
 #include "logging.h"
-#include <colorcorrection/gammaramp.h>
 
 namespace KWin
 {
@@ -114,9 +113,15 @@ bool DrmCrtc::blank()
     return false;
 }
 
-bool DrmCrtc::setGammaRamp(const ColorCorrect::GammaRamp &gamma) {
-    bool isError = drmModeCrtcSetGamma(m_backend->fd(), m_id, gamma.size,
-                                gamma.red, gamma.green, gamma.blue);
+bool DrmCrtc::setGammaRamp(const GammaRamp &gamma)
+{
+    uint16_t *red = const_cast<uint16_t *>(gamma.red());
+    uint16_t *green = const_cast<uint16_t *>(gamma.green());
+    uint16_t *blue = const_cast<uint16_t *>(gamma.blue());
+
+    const bool isError = drmModeCrtcSetGamma(m_backend->fd(), m_id,
+        gamma.size(), red, green, blue);
+
     return !isError;
 }
 

plugins/platforms/drm/drm_object_crtc.h

@@ -25,13 +25,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 namespace KWin
 {
 
-namespace ColorCorrect {
-struct GammaRamp;
-}
-
 class DrmBackend;
 class DrmBuffer;
 class DrmDumbBuffer;
+class GammaRamp;
 
 class DrmCrtc : public DrmObject
 {
@@ -67,10 +64,10 @@ public:
     void flipBuffer();
     bool blank();
 
-    int getGammaRampSize() const {
+    int gammaRampSize() const {
         return m_gammaRampSize;
     }
-    bool setGammaRamp(const ColorCorrect::GammaRamp &gamma);
+    bool setGammaRamp(const GammaRamp &gamma);
 
 private:
     int m_resIndex;

plugins/platforms/drm/drm_output.cpp

@@ -1201,12 +1201,12 @@ void DrmOutput::automaticRotation()
     emit screens()->changed();
 }
 
-int DrmOutput::getGammaRampSize() const
+int DrmOutput::gammaRampSize() const
 {
-    return m_crtc->getGammaRampSize();
+    return m_crtc->gammaRampSize();
 }
 
-bool DrmOutput::setGammaRamp(const ColorCorrect::GammaRamp &gamma)
+bool DrmOutput::setGammaRamp(const GammaRamp &gamma)
 {
     return m_crtc->setGammaRamp(gamma);
 }

plugins/platforms/drm/drm_output.h

@@ -133,8 +133,8 @@ private:
     void transform(KWayland::Server::OutputDeviceInterface::Transform transform) override;
     void automaticRotation();
 
-    int getGammaRampSize() const override;
-    bool setGammaRamp(const ColorCorrect::GammaRamp &gamma) override;
+    int gammaRampSize() const override;
+    bool setGammaRamp(const GammaRamp &gamma) override;
     QMatrix4x4 matrixDisplay(const QSize &s) const;
 
     DrmBackend *m_backend;

plugins/platforms/virtual/virtual_output.h

@@ -41,10 +41,10 @@ public:
 
     void setGeometry(const QRect &geo);
 
-    int getGammaRampSize() const override {
+    int gammaRampSize() const override {
         return m_gammaSize;
     }
-    bool setGammaRamp(const ColorCorrect::GammaRamp &gamma) override {
+    bool setGammaRamp(const GammaRamp &gamma) override {
         Q_UNUSED(gamma);
         return m_gammaResult;
     }

plugins/platforms/x11/standalone/x11_output.cpp

@@ -61,4 +61,31 @@ void X11Output::setRefreshRate(int set)
     m_refreshRate = set;
 }
 
+int X11Output::gammaRampSize() const
+{
+    return m_gammaRampSize;
+}
+
+bool X11Output::setGammaRamp(const GammaRamp &gamma)
+{
+    if (m_crtc == XCB_NONE) {
+        return false;
+    }
+
+    xcb_randr_set_crtc_gamma(connection(), m_crtc, gamma.size(), gamma.red(),
+        gamma.green(), gamma.blue());
+
+    return true;
+}
+
+void X11Output::setCrtc(xcb_randr_crtc_t crtc)
+{
+    m_crtc = crtc;
+}
+
+void X11Output::setGammaRampSize(int size)
+{
+    m_gammaRampSize = size;
+}
+
 }

plugins/platforms/x11/standalone/x11_output.h

@@ -26,6 +26,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QObject>
 #include <QRect>
 
+#include <xcb/randr.h>
+
 namespace KWin
 {
 
@@ -35,6 +37,7 @@ namespace KWin
 class KWIN_EXPORT X11Output : public AbstractOutput
 {
     Q_OBJECT
+
 public:
     explicit X11Output(QObject *parent = nullptr);
     virtual ~X11Output() = default;
@@ -53,10 +56,23 @@ public:
     int refreshRate() const override;
     void setRefreshRate(int set);
 
+    /**
+     * The size of gamma lookup table.
+     **/
+    int gammaRampSize() const override;
+    bool setGammaRamp(const GammaRamp &gamma) override;
+
 private:
+    void setCrtc(xcb_randr_crtc_t crtc);
+    void setGammaRampSize(int size);
+
+    xcb_randr_crtc_t m_crtc = XCB_NONE;
     QString m_name;
     QRect m_geometry;
+    int m_gammaRampSize;
     int m_refreshRate;
+
+    friend class X11StandalonePlatform;
 };
 
 }

plugins/platforms/x11/standalone/x11_platform.cpp

@@ -81,6 +81,8 @@ X11StandalonePlatform::X11StandalonePlatform(QObject *parent)
             }
         }
     );
+
+    setSupportsGammaControl(true);
 }
 
 X11StandalonePlatform::~X11StandalonePlatform()
@@ -456,6 +458,7 @@ void X11StandalonePlatform::doUpdateOutputs()
 {
     auto fallback = [this]() {
         auto *o = new X11Output(this);
+        o->setGammaRampSize(0);
         o->setRefreshRate(-1.0f);
         o->setName(QStringLiteral("Xinerama"));
         m_outputs << o;
@@ -514,14 +517,23 @@ void X11StandalonePlatform::doUpdateOutputs()
 
         const QRect geo = info.rect();
         if (geo.isValid()) {
+            xcb_randr_crtc_t crtc = crtcs[i];
+
+            // TODO: Perhaps the output has to save the inherited gamma ramp and
+            // restore it during tear down. Currently neither standalone x11 nor
+            // drm platform do this.
+            Xcb::RandR::CrtcGamma gamma(crtc);
+
             auto *o = new X11Output(this);
+            o->setCrtc(crtc);
+            o->setGammaRampSize(gamma.isNull() ? 0 : gamma->size);
             o->setGeometry(geo);
             o->setRefreshRate(refreshRate);
 
             QString name;
             for (int j = 0; j < info->num_outputs; ++j) {
                 Xcb::RandR::OutputInfo outputInfo(outputInfos.at(j));
-                if (crtcs[i] == outputInfo->crtc) {
+                if (crtc == outputInfo->crtc) {
                     name = outputInfo.name();
                     break;
                 }