Added gamma correction value to dw::core::ImgBuf.

6 files changed, 36 insertions, 23 deletions

diff --git a/dw/fltkimgbuf.cc b/dw/fltkimgbuf.cc
index a63a9a89..4b93601f 100644
--- a/dw/fltkimgbuf.cc
+++ b/dw/fltkimgbuf.cc
@@ -39,19 +39,21 @@ static bool excessiveImageDimensions (int width, int height)
       width > IMAGE_MAX_AREA / height;
 }
 
-FltkImgbuf::FltkImgbuf (Type type, int width, int height)
+FltkImgbuf::FltkImgbuf (Type type, int width, int height, double gamma)
 {
    _MSG("FltkImgbuf: new root %p\n", this);
-   init (type, width, height, NULL);
+   init (type, width, height, gamma, NULL);
 }
 
-FltkImgbuf::FltkImgbuf (Type type, int width, int height, FltkImgbuf *root)
+FltkImgbuf::FltkImgbuf (Type type, int width, int height, double gamma,
+                        FltkImgbuf *root)
 {
    _MSG("FltkImgbuf: new scaled %p, root is %p\n", this, root);
-   init (type, width, height, root);
+   init (type, width, height, gamma, root);
 }
 
-void FltkImgbuf::init (Type type, int width, int height, FltkImgbuf *root)
+void FltkImgbuf::init (Type type, int width, int height, double gamma,
+                       FltkImgbuf *root)
 {
    if (excessiveImageDimensions (width, height)) {
       // Excessive image sizes which would cause crashes due to too
@@ -60,7 +62,7 @@ void FltkImgbuf::init (Type type, int width, int height, FltkImgbuf *root)
       // 1 size.
       MSG("FltkImgbuf::init: suspicious image size request %d x %d\n",
           width, height);
-      init (type, 1, 1, root);
+      init (type, 1, 1, gamma, root);
    } else if (width > MAX_WIDTH) {
       // Too large dimensions cause dangerous overflow errors, so we
       // limit dimensions to harmless values.
@@ -69,15 +71,19 @@ void FltkImgbuf::init (Type type, int width, int height, FltkImgbuf *root)
       // the negative value -1.
 
       MSG("FltkImgbuf::init: cannot handle large width %d\n", width);
-      init (type, MAX_WIDTH, height, root);
+      init (type, MAX_WIDTH, height, gamma, root);
    } else if (height > MAX_HEIGHT) {
       MSG("FltkImgbuf::init: cannot handle large height %d\n", height);
-      init (type, width, MAX_HEIGHT, root);
+      init (type, width, MAX_HEIGHT, gamma, root);
+   } else if (gamma <= 0) {
+      MSG("FltkImgbuf::init: non-positive gamma %g\n", gamma);
+      init (type, width, height, 1, root);
    } else {
       this->root = root;
       this->type = type;
       this->width = width;
       this->height = height;
+      this->gamma = gamma;
 
       // TODO: Maybe this is only for root buffers
       switch (type) {
@@ -85,7 +91,8 @@ void FltkImgbuf::init (Type type, int width, int height, FltkImgbuf *root)
       case RGB:  bpp = 3; break;
       default:   bpp = 1; break;
       }
-      _MSG("FltkImgbuf::init width=%d height=%d bpp=%d\n", width, height, bpp);
+      _MSG("FltkImgbuf::init width=%d height=%d bpp=%d gamma=%g\n",
+           width, height, bpp, gamma);
       rawdata = new uchar[bpp * width * height];
       // Set light-gray as interim background color.
       memset(rawdata, 222, width*height*bpp);
@@ -323,7 +330,7 @@ core::Imgbuf* FltkImgbuf::getScaledBuf (int width, int height)
    }
 
    // This size is not yet used, so a new buffer has to be created.
-   FltkImgbuf *sb = new FltkImgbuf (type, width, height, this);
+   FltkImgbuf *sb = new FltkImgbuf (type, width, height, gamma, this);
    scaledBuffers->append (sb);
    return sb;
 }
diff --git a/dw/fltkimgbuf.hh b/dw/fltkimgbuf.hh
index d862eece..f7455807 100644
--- a/dw/fltkimgbuf.hh
+++ b/dw/fltkimgbuf.hh
@@ -18,6 +18,7 @@ private:
 
    int width, height;
    Type type;
+   double gamma;
 
 //{
    int bpp;
@@ -28,8 +29,9 @@ private:
    // the image buffer.
    lout::misc::BitSet *copiedRows;
 
-   FltkImgbuf (Type type, int width, int height, FltkImgbuf *root);
-   void init (Type type, int width, int height, FltkImgbuf *root);
+   FltkImgbuf (Type type, int width, int height, double gamma,
+               FltkImgbuf *root);
+   void init (Type type, int width, int height, double gamma, FltkImgbuf *root);
    int scaledY(int ySrc);
    int backscaledY(int yScaled);
    int isRoot() { return (root == NULL); }
@@ -39,7 +41,7 @@ protected:
    ~FltkImgbuf ();
 
 public:
-   FltkImgbuf (Type type, int width, int height);
+   FltkImgbuf (Type type, int width, int height, double gamma);
 
    void setCMap (int *colors, int num_colors);
    inline void scaleRow (int row, const core::byte *data);
diff --git a/dw/fltkplatform.cc b/dw/fltkplatform.cc
index 7dd87a18..1d77e289 100644
--- a/dw/fltkplatform.cc
+++ b/dw/fltkplatform.cc
@@ -704,9 +704,9 @@ void FltkPlatform::copySelection(const char *text)
 }
 
 core::Imgbuf *FltkPlatform::createImgbuf (core::Imgbuf::Type type,
-                                          int width, int height)
+                                          int width, int height, double gamma)
 {
-   return new FltkImgbuf (type, width, height);
+   return new FltkImgbuf (type, width, height, gamma);
 }
 
 core::ui::ResourceFactory *FltkPlatform::getResourceFactory ()
diff --git a/dw/fltkplatform.hh b/dw/fltkplatform.hh
index 64605b68..2fb95633 100644
--- a/dw/fltkplatform.hh
+++ b/dw/fltkplatform.hh
@@ -169,7 +169,8 @@ public:
    core::style::Tooltip *createTooltip (const char *text);
    void cancelTooltip();
 
-   core::Imgbuf *createImgbuf (core::Imgbuf::Type type, int width, int height);
+   core::Imgbuf *createImgbuf (core::Imgbuf::Type type, int width, int height,
+                               double gamma);
 
    void copySelection(const char *text);
 
diff --git a/dw/layout.hh b/dw/layout.hh
index d3ace03a..51d764a4 100644
--- a/dw/layout.hh
+++ b/dw/layout.hh
@@ -358,9 +358,10 @@ public:
       return platform->cancelTooltip ();
    }
 
-   inline Imgbuf *createImgbuf (Imgbuf::Type type, int width, int height)
+   inline Imgbuf *createImgbuf (Imgbuf::Type type, int width, int height,
+                                double gamma)
    {
-      return platform->createImgbuf (type, width, height);
+      return platform->createImgbuf (type, width, height, gamma);
    }
 
    inline void copySelection(const char *text)
diff --git a/dw/platform.hh b/dw/platform.hh
index 1e16dcfe..532f4cf9 100644
--- a/dw/platform.hh
+++ b/dw/platform.hh
@@ -146,12 +146,14 @@ public:
     */
    virtual void cancelTooltip () = 0;
 
-   /*
-    * --------------------
-    *    Image Buffers
-    * --------------------
+   /**
+    * \brief Create a (platform speficic) image buffer.
+    *
+    * "gamma" is the value by which the image data is already
+    * corrected.
     */
-   virtual Imgbuf *createImgbuf (Imgbuf::Type type, int width, int height) = 0;
+   virtual Imgbuf *createImgbuf (Imgbuf::Type type, int width, int height,
+                                 double gamma) = 0;
 
    /**
     * \brief Copy selected text (0-terminated).