--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancStone/Sources/OpenGL/OpenGLShader.cpp	Tue Jul 07 16:21:02 2020 +0200
@@ -0,0 +1,135 @@
+/**
+ * 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 "OpenGLShader.h"
+
+#include <OrthancException.h>
+
+namespace OrthancStone
+{
+  namespace OpenGL
+  {
+    static GLuint CompileShader(GLenum type,
+                                const std::string& source) 
+    {
+      // Create shader object
+      const GLchar* sourceString[1];
+      GLint sourceStringLengths[1];
+
+      sourceString[0] = source.c_str();
+      sourceStringLengths[0] = static_cast<GLint>(source.length());
+      GLuint shader = glCreateShader(type);
+      ORTHANC_OPENGL_CHECK("glCreateShader");
+
+      if (shader == 0)
+      {
+        throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError,
+                                        "Cannot create an OpenGL shader");
+      }
+      else
+      {
+        // Assign and compile the source to the shader object
+        glShaderSource(shader, 1, sourceString, sourceStringLengths);
+        ORTHANC_OPENGL_CHECK("glShaderSource");
+        glCompileShader(shader);
+        ORTHANC_OPENGL_CHECK("glCompileShader");
+
+        // Check if there were errors
+        int infoLen = 0;
+        glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLen);
+        ORTHANC_OPENGL_CHECK("glGetShaderiv");
+
+        if (infoLen > 1)  // Might be equal to 1, which amounts to no error
+        {
+          std::string infoLog;
+          infoLog.resize(infoLen + 1);
+          glGetShaderInfoLog(shader, infoLen, NULL, &infoLog[0]);
+          ORTHANC_OPENGL_CHECK("glGetShaderInfoLog");
+          ORTHANC_OPENGL_TRACE_CURRENT_CONTEXT("About to call glDeleteShader");
+          glDeleteShader(shader);
+          ORTHANC_OPENGL_CHECK("glDeleteShader");
+
+          throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError,
+                                          "Error while creating an OpenGL shader: " + infoLog);
+        }
+        else
+        {
+          return shader;
+        }
+      }
+    }
+
+
+    OpenGLShader::OpenGLShader(GLenum type,
+                               const std::string& source)
+    {
+      shader_ = CompileShader(type, source);
+      isValid_ = true;
+    }
+
+    
+    OpenGLShader::~OpenGLShader()
+    {
+      try
+      {
+        if (isValid_)
+        {
+          ORTHANC_OPENGL_TRACE_CURRENT_CONTEXT("About to call glDeleteShader");
+          glDeleteShader(shader_);
+          ORTHANC_OPENGL_CHECK("glDeleteShader");
+        }
+      }
+      catch (const Orthanc::OrthancException& e)
+      {
+        if (e.HasDetails())
+        {
+          LOG(ERROR) << "OrthancException in ~OpenGLShader: " << e.What() << " Details: " << e.GetDetails();
+        }
+        else
+        {
+          LOG(ERROR) << "OrthancException in ~OpenGLShader: " << e.What();
+        }
+      }
+      catch (const std::exception& e)
+      {
+        LOG(ERROR) << "std::exception in ~OpenGLShader: " << e.what();
+      }
+      catch (...)
+      {
+        LOG(ERROR) << "Unknown exception in ~OpenGLShader";
+      }
+    }
+
+    GLuint OpenGLShader::Release()
+    {
+      if (isValid_)
+      {
+        isValid_ = false;
+        return shader_;
+      }
+      else
+      {
+        LOG(ERROR) << "OpenGLShader::Release(): (!isValid_)";
+        throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
+      }
+    }
+  }
+}