From 09d41789da6e69839fe54195f9f391e32ef43ba7 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Sun, 14 Apr 2002 13:41:13 +0000
Subject: [PATCH] Fixes to osg::Image::createImage(..), and addition of code to
 Viewer.cpp to support output of screen snapshot via 'O'.

---
 include/osg/Image                      |  2 --
 src/osg/Image.cpp                      | 28 +++++++++++---------------
 src/osgGLUT/Viewer.cpp                 | 24 ++++++++++++++++++++++
 src/osgPlugins/bmp/ReaderWriterBMP.cpp | 24 +++++++++++-----------
 4 files changed, 48 insertions(+), 30 deletions(-)

diff --git a/include/osg/Image b/include/osg/Image
index 87320d400..0e25c536f 100644
--- a/include/osg/Image
+++ b/include/osg/Image
@@ -137,8 +137,6 @@ class SG_EXPORT Image : public Object
 
         Image& operator = (const Image&) { return *this; }
 
-        void computePixelSize();
-
         std::string _fileName;
         int _s, _t, _r;
         GLint _internalTextureFormat;
diff --git a/src/osg/Image.cpp b/src/osg/Image.cpp
index 294e78b44..1ad4ff957 100644
--- a/src/osg/Image.cpp
+++ b/src/osg/Image.cpp
@@ -63,11 +63,6 @@ void Image::setFileName(const std::string& fileName)
     _fileName = fileName;
 }
 
-
-void Image::computePixelSize()
-{
-}
-
 #ifndef GL_VERSION_1_2
     /* 1.2 definitions...*/
     #define GL_BGR					0x80E0
@@ -130,19 +125,19 @@ const unsigned int Image::computeNumComponents(GLenum type)
 
 const unsigned int Image::computePixelSizeInBits(GLenum format,GLenum type)
 {
-    switch(format)
+    switch(type)
     {
-        case(GL_BITMAP): return computeNumComponents(type);
+        case(GL_BITMAP): return computeNumComponents(format);
         
         case(GL_BYTE):
-        case(GL_UNSIGNED_BYTE): return 8*computeNumComponents(type);
+        case(GL_UNSIGNED_BYTE): return 8*computeNumComponents(format);
         
         case(GL_SHORT):
-        case(GL_UNSIGNED_SHORT): return 16*computeNumComponents(type);
+        case(GL_UNSIGNED_SHORT): return 16*computeNumComponents(format);
         
         case(GL_INT):
         case(GL_UNSIGNED_INT):
-        case(GL_FLOAT): return 32*computeNumComponents(type);
+        case(GL_FLOAT): return 32*computeNumComponents(format);
     
     
         case(GL_UNSIGNED_BYTE_3_3_2): 
@@ -159,7 +154,7 @@ const unsigned int Image::computePixelSizeInBits(GLenum format,GLenum type)
         case(GL_UNSIGNED_INT_8_8_8_8_REV):
         case(GL_UNSIGNED_INT_10_10_10_2):
         case(GL_UNSIGNED_INT_2_10_10_10_REV): return 32;
-        default: return false;
+        default: return 0;
     }    
 
 }
@@ -169,7 +164,7 @@ const unsigned int Image::computeRowWidthInBytes(int width,GLenum format,GLenum
     unsigned int pixelSize = computePixelSizeInBits(format,type);
     int widthInBits = width*pixelSize;
     int packingInBits = packing*8;
-    return (widthInBits/packingInBits + (widthInBits%packingInBits)?1:0)*packing;
+    return (widthInBits/packingInBits + ((widthInBits%packingInBits)?1:0))*packing;
 }
 
 
@@ -185,7 +180,10 @@ void Image::createImage(int s,int t,int r,
     {
         if (_data) ::free(_data);
         
-        _data = (unsigned char *)malloc (newTotalSize);
+        if (newTotalSize)
+            _data = (unsigned char *)malloc (newTotalSize);
+        else
+            _data = 0L;
     }
 
     if (_data)
@@ -231,8 +229,6 @@ void Image::setImage(int s,int t,int r,
     _data = data;
     _packing = packing;
         
-    computePixelSize();
-
     // test scaling...
     //    scaleImageTo(16,16,_r);
     
@@ -270,7 +266,7 @@ void Image::scaleImage(const int s,const int t,const int r)
 
     // need to sort out what size to really use...
     unsigned char* newData = (unsigned char *)malloc(newTotalSize);
-    if (newData)
+    if (!newData)
     {
         // should we throw an exception???  Just return for time being.
         notify(FATAL) << "Error Image::scaleImage() do not succeed : out of memory."<<std::endl;
diff --git a/src/osgGLUT/Viewer.cpp b/src/osgGLUT/Viewer.cpp
index db47fe919..581ec0aa6 100644
--- a/src/osgGLUT/Viewer.cpp
+++ b/src/osgGLUT/Viewer.cpp
@@ -1053,6 +1053,30 @@ void Viewer::keyboard(unsigned char key, int x, int y)
             help(osg::notify(osg::NOTICE));
             break;
 
+
+        case 'O' :
+            {
+                osg::Viewport* viewport = sceneView->getViewport();
+                if (viewport)
+                {
+
+                    std::string filename("screenshot.bmp");
+
+                    glReadBuffer(GL_FRONT);
+                    osg::ref_ptr<Image> image = osgNew osg::Image;
+                    image->readPixels(viewport->x(),viewport->y(),viewport->width(),viewport->height(),
+                                      GL_RGB,GL_UNSIGNED_BYTE);
+
+                    osgDB::writeImageFile(*image,filename);
+
+                    osg::notify(osg::NOTICE) << "Saved screen image to `"<<filename<<"`"<< std::endl;
+                }
+                else
+                {
+                    osg::notify(osg::NOTICE) << "Cannot create snapshot of screen, no valid viewport attached"<< std::endl;
+                }
+            }
+            break;
         case 'i' :
         case 'r' :
         {
diff --git a/src/osgPlugins/bmp/ReaderWriterBMP.cpp b/src/osgPlugins/bmp/ReaderWriterBMP.cpp
index b278c8f2a..146c0bfc7 100644
--- a/src/osgPlugins/bmp/ReaderWriterBMP.cpp
+++ b/src/osgPlugins/bmp/ReaderWriterBMP.cpp
@@ -171,11 +171,11 @@ int *numComponents_ret)
         if (swap) swapbyte(&infsize);
         unsigned char *hdr=new unsigned char[infsize]; // to hold the new header
         fread((char *)hdr, 1,infsize-sizeof(long), fp);
-        unsigned long hsiz=sizeof(inf); // minimum of structure size & 
+        long hsiz=sizeof(inf); // minimum of structure size & 
         if(infsize<=hsiz) hsiz=infsize;
         memcpy(&inf,hdr, hsiz/*-sizeof(long)*/); // copy only the bytes I can cope with
         delete [] hdr;
-        osg::notify(osg::WARN) << "loading "<<filename <<" "<<swap<<" "<<infsize<< " "<<sizeof(inf) << " "<<sizeof(bmpheader) << std::endl;
+        osg::notify(osg::INFO) << "loading "<<filename <<" "<<swap<<" "<<infsize<< " "<<sizeof(inf) << " "<<sizeof(bmpheader) << std::endl;
         if (swap) { // inverse the field of the header which need swapping
             swapbyte(&hd.siz[0]);
             swapbyte(&hd.siz[1]);
@@ -195,7 +195,7 @@ int *numComponents_ret)
             inf.Colorbits=cbits;
             inf.ColorUsed=(long)pow(2.0,(double)inf.Colorbits); // infer the colours
         }
-        osg::notify(osg::WARN) << "readbmp " <<inf.width<< " "<<inf.height << std::endl;
+        osg::notify(osg::INFO) << "readbmp " <<inf.width<< " "<<inf.height << std::endl;
         long size = hd.siz[1]+hd.siz[0]*65536;
         int ncpal=4; // default number of colours per palette entry
         size -= sizeof(bmpheader)+infsize;
@@ -334,13 +334,13 @@ class ReaderWriterBMP : public osgDB::ReaderWriter
             return pOsgImage;
 
         }
-        virtual WriteResult writeImage(const osg::Image &img,const std::string& fileName, const osgDB::ReaderWriter::Options* op)
+        virtual WriteResult writeImage(const osg::Image &img,const std::string& fileName, const osgDB::ReaderWriter::Options*)
         {
             FILE *fp = fopen(fileName.c_str(), "wb");
             if (!fp) return WriteResult::ERROR_IN_WRITING_FILE;
             // its easier for me to write a binary write using stdio than streams
             struct bmpheader hd;
-            unsigned long nx=img.s(),ny=img.t(), ndep=img.r();
+            unsigned long nx=img.s(),ny=img.t(); //  unsigned long ndep=img.r();
             unsigned long size, wordsPerScan;
             long infsize;    //size of BMPinfo in bytes
             wordsPerScan=(nx*3+3)/4; // rounds up to next 32 bit boundary
@@ -353,15 +353,15 @@ class ReaderWriterBMP : public osgDB::ReaderWriter
             hd.siz[1]=(size&0xffff); // low word
             fwrite(&hd, sizeof(hd), 1, fp);
             struct BMPInfo inf;
-            osg::notify(osg::WARN) << "sizes "<<size << " "<<sizeof(inf)<< std::endl;
+            osg::notify(osg::INFO) << "sizes "<<size << " "<<sizeof(inf)<< std::endl;
             inf.width=nx;   //width of the image in pixels
             inf.height=ny;    //   height of the image in pixels
             inf.planes=1;       //:word: number of planes (always 1)
             inf.Colorbits=24;       //word: number of bits used to describe color in each pixel
             inf.compression=0;  //compression used windows says 0= no compression
             inf.ImageSize=size;    //nx*ny*3; //image size in bytes
-            inf.XpixPerMeter=.001; //pixels per meter in X
-            inf.YpixPerMeter=.001; //pixels per meter in Y
+            inf.XpixPerMeter=1000; //pixels per meter in X
+            inf.YpixPerMeter=1000; //pixels per meter in Y
             inf.ColorUsed=0;   //number of colors used
             inf.Important=0;   //number of "important" colors
    // inf.os2stuff[6]; // allows os2.1 with 64 bytes to be read.  Dont know what these are yet.
@@ -369,16 +369,16 @@ class ReaderWriterBMP : public osgDB::ReaderWriter
             fwrite(&infsize, sizeof(long), 1, fp);
             fwrite(&inf, sizeof(inf), 1, fp); // one dword shorter than the structure defined by MS
               // the infsize value (above) completes the structure.
-            osg::notify(osg::WARN) << "save screen "<<fileName <<inf.width<< " "<<inf.height << std::endl;
-            osg::notify(osg::WARN) << "sizes "<<size << " "<<infsize <<" "<<sizeof(inf)<< std::endl;
+            osg::notify(osg::INFO) << "save screen "<<fileName <<inf.width<< " "<<inf.height << std::endl;
+            osg::notify(osg::INFO) << "sizes "<<size << " "<<infsize <<" "<<sizeof(inf)<< std::endl;
             // now output the bitmap
             // 1) swap Blue with Red - needed for Windoss.
             unsigned char *dta=new unsigned char[size];
             unsigned char tmp;
             memcpy(dta,img.data(),size*sizeof(unsigned char));
-            for(int i=0;i<ny;i++) { // per scanline
+            for(unsigned int i=0;i<ny;i++) { // per scanline
                 int ioff=4*wordsPerScan*i;
-                for(int j=0;j<nx;j++) {
+                for(unsigned int j=0;j<nx;j++) {
                 tmp=dta[3*j+ioff]; // swap r with b,  thanks to good ole Bill - 
   //"Let's use BGR it's more logical than rgb which everyone else uses."
                 dta[3*j+ioff]=dta[3*j+ioff+2];