Ticket #1624: galleryopengl.diff

glsingleview.cpp

@@ -80 +80 @@
     gContext->GetScreenSettings(xbase, screenwidth, wmult, 
                                 ybase, screenheight, hmult);
 
-    m_w = min(1024, 1 << (int)ceil(log((float)screenwidth)/log((float)2)));
-    m_h = min(1024, 1 << (int)ceil(log((float)screenheight)/log((float)2)));
+    m_w = NearestGLTextureSize(screenwidth);
+    m_h = NearestGLTextureSize(screenheight);
 
     // --------------------------------------------------------------------
 
@@ -179 +179 @@
     }
 }
 
+int GLSingleView::NearestGLTextureSize(int v)
+{
+    int n = 0, last = 0;
+    int s;
+
+    for (int s = 0; s < 32; ++s)
+    {
+        if (((v >> s) & 1) == 1)
+        {
+            ++n;
+            last = s;
+        }
+    }
+
+    if (n > 1)
+        s = 1 << (last + 1);
+    else
+        s = 1 << last;
+
+    if (s > m_maxTexDim)
+        s = m_maxTexDim;
+
+    return s;
+}
+
+
 GLSingleView::~GLSingleView()
 {
     if (m_sequence)
@@ -220 +246 @@
     // Enable perspective vision
     glClearDepth(1.0f);
 
+    GLint param;
+    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &param);
+    m_maxTexDim = param;
+
     loadImage();
 }
 

glsingleview.h

@@ -102 +102 @@
 
     GLuint        m_texInfo;
     bool          m_showInfo;
-    
+    int           m_maxTexDim;    
+
     int           m_i;
     int           m_dir;
     float         m_points[40][40][3];
@@ -114 +115 @@
     SequenceBase               *m_sequence;
 
 private:
-    
+
+    int NearestGLTextureSize(int);    
     void  advanceFrame();
     void  retreatFrame();
     void  loadImage();