--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancStone/Sources/OpenGL/OpenGLTexture.cpp	Tue Jul 07 16:21:02 2020 +0200
@@ -0,0 +1,145 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 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
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "OpenGLTexture.h"
+#include "IOpenGLContext.h"
+
+#include <OrthancException.h>
+
+namespace OrthancStone
+{
+  namespace OpenGL
+  {
+    OpenGLTexture::OpenGLTexture(OpenGL::IOpenGLContext& context)
+      : width_(0)
+      , height_(0)
+      , context_(context)
+    {
+      if (!context_.IsContextLost())
+      {
+        // Generate a texture object
+        glGenTextures(1, &texture_);
+        if (texture_ == 0)
+        {
+          throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError,
+            "Cannot create an OpenGL program");
+        }
+      }
+    }
+
+    OpenGLTexture::~OpenGLTexture()
+    {
+      try
+      {
+        if (!context_.IsContextLost())
+        {
+          assert(texture_ != 0);
+          ORTHANC_OPENGL_TRACE_CURRENT_CONTEXT("About to call glDeleteTextures");
+          glDeleteTextures(1, &texture_);
+        }
+      }
+      catch (const Orthanc::OrthancException& e)
+      {
+        if (e.HasDetails())
+        {
+          LOG(ERROR) << "OrthancException in ~OpenGLTexture: " << e.What() << " Details: " << e.GetDetails();
+        }
+        else
+        {
+          LOG(ERROR) << "OrthancException in ~OpenGLTexture: " << e.What();
+        }
+      }
+      catch (const std::exception& e)
+      {
+        LOG(ERROR) << "std::exception in ~OpenGLTexture: " << e.what();
+      }
+      catch (...)
+      {
+        LOG(ERROR) << "Unknown exception in ~OpenGLTexture";
+      }
+    }
+
+    void OpenGLTexture::Load(const Orthanc::ImageAccessor& image,
+                             bool isLinearInterpolation)
+    {
+      if (!context_.IsContextLost())
+      {
+        glPixelStorei(GL_UNPACK_ALIGNMENT, 1); // Disable byte-alignment restriction
+
+        if (image.GetPitch() != image.GetBytesPerPixel() * image.GetWidth())
+        {
+          throw Orthanc::OrthancException(Orthanc::ErrorCode_NotImplemented,
+            "Unsupported non-zero padding");
+        }
+
+        // Bind it
+        glActiveTexture(GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, texture_);
+
+        GLenum sourceFormat, internalFormat;
+
+        switch (image.GetFormat())
+        {
+        case Orthanc::PixelFormat_Grayscale8:
+          sourceFormat = GL_RED;
+          internalFormat = GL_RED;
+          break;
+
+        case Orthanc::PixelFormat_RGB24:
+          sourceFormat = GL_RGB;
+          internalFormat = GL_RGB;
+          break;
+
+        case Orthanc::PixelFormat_RGBA32:
+          sourceFormat = GL_RGBA;
+          internalFormat = GL_RGBA;
+          break;
+
+        default:
+          throw Orthanc::OrthancException(Orthanc::ErrorCode_NotImplemented,
+            "No support for this format in OpenGL textures: " +
+            std::string(EnumerationToString(image.GetFormat())));
+        }
+
+        width_ = image.GetWidth();
+        height_ = image.GetHeight();
+
+        GLint interpolation = (isLinearInterpolation ? GL_LINEAR : GL_NEAREST);
+
+        // Load the texture from the image buffer
+        glTexImage2D(GL_TEXTURE_2D, 0, internalFormat, image.GetWidth(), image.GetHeight(),
+          0, sourceFormat, GL_UNSIGNED_BYTE, image.GetBuffer());
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, interpolation);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, interpolation);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+      }
+    }
+
+
+    void OpenGLTexture::Bind(GLint location)
+    {
+      glActiveTexture(GL_TEXTURE0);
+      glBindTexture(GL_TEXTURE_2D, texture_);
+      glUniform1i(location, 0 /* texture unit */);
+    }
+  }
+}