change from glew to epoxy

because that works under wayland out of the box and gtk3 uses it already

Change-Id: Iefaac31e325534a81a5389f752804af917c1baef
Reviewed-on: https://gerrit.libreoffice.org/31213
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

2 files changed, 10 insertions, 32 deletions

diff --git a/vcl/source/opengl/OpenGLContext.cxx b/vcl/source/opengl/OpenGLContext.cxx
index 93bde70bcdf7..c04a0cf0c7fc 100644
--- a/vcl/source/opengl/OpenGLContext.cxx
+++ b/vcl/source/opengl/OpenGLContext.cxx
@@ -7,7 +7,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-#include <config_opengl.h>
 #include <chrono>
 
 #include <vcl/opengl/OpenGLContext.hxx>
@@ -205,13 +204,8 @@ extern "C" void
 APIENTRY
 #endif
 debug_callback(GLenum source, GLenum type, GLuint id,
-        GLenum severity, GLsizei , const GLchar* message,
-#if HAVE_GLEW_1_12
-        const GLvoid*
-#else
-        GLvoid*
-#endif
-        )
+               GLenum severity, GLsizei , const GLchar* message,
+               const GLvoid*)
 {
     // ignore Nvidia's 131218: "Program/shader state performance warning: Fragment Shader is going to be recompiled because the shader key based on GL state mismatches."
     // the GLSL compiler is a bit too aggressive in optimizing the state based on the current OpenGL state
@@ -280,30 +274,14 @@ OUString getGLString(GLenum eGlEnum)
     return sString;
 }
 
-bool OpenGLContext::InitGLEW()
+bool OpenGLContext::InitGL()
 {
-    static bool bGlewInit = false;
-    if(!bGlewInit)
-    {
-        OpenGLZone aZone;
-
-        glewExperimental = GL_TRUE;
-        GLenum err = glewInit();
-        if (err != GLEW_OK)
-        {
-            SAL_WARN("vcl.opengl", "Failed to initialize GLEW: " << glewGetErrorString(err));
-            return false;
-        }
-        else
-            bGlewInit = true;
-    }
-
     VCL_GL_INFO("OpenGLContext::ImplInit----end");
     VCL_GL_INFO("Vendor: " << getGLString(GL_VENDOR) << " Renderer: " << getGLString(GL_RENDERER) << " GL version: " << OpenGLHelper::getGLVersion());
     mbInitialized = true;
 
     // I think we need at least GL 3.0
-    if (!GLEW_VERSION_3_0)
+    if (epoxy_gl_version() < 30)
     {
         SAL_WARN("vcl.opengl", "We don't have at least OpenGL 3.0");
         return false;
@@ -319,11 +297,11 @@ bool OpenGLContext::InitGLEW()
     return true;
 }
 
-void OpenGLContext::InitGLEWDebugging()
+void OpenGLContext::InitGLDebugging()
 {
 #ifdef DBG_UTIL
     // only enable debug output in dbgutil build
-    if( GLEW_ARB_debug_output)
+    if (epoxy_has_gl_extension("GL_ARB_debug_output"))
     {
         OpenGLZone aZone;
 
diff --git a/vcl/source/opengl/OpenGLHelper.cxx b/vcl/source/opengl/OpenGLHelper.cxx
index f07e7dcbfa8e..9b91415d2392 100644
--- a/vcl/source/opengl/OpenGLHelper.cxx
+++ b/vcl/source/opengl/OpenGLHelper.cxx
@@ -401,7 +401,7 @@ GLint OpenGLHelper::LoadShaders(const OUString& rVertexShaderName,
         aGeometryShaderSource = getShaderSource(rGeometryShaderName);
 
     GLint bBinaryResult = GL_FALSE;
-    if( GLEW_ARB_get_program_binary && !rDigest.isEmpty() )
+    if (epoxy_has_gl_extension("GL_ARB_get_program_binary") && !rDigest.isEmpty())
     {
         OString aFileName =
                 createFileName(rVertexShaderName, rFragmentShaderName, rGeometryShaderName, rDigest);
@@ -473,7 +473,7 @@ GLint OpenGLHelper::LoadShaders(const OUString& rVertexShaderName,
     if (bHasGeometryShader)
         glAttachShader(ProgramID, GeometryShaderID);
 
-    if( GLEW_ARB_get_program_binary && !rDigest.isEmpty() )
+    if (epoxy_has_gl_extension("GL_ARB_get_program_binary") && !rDigest.isEmpty())
     {
         glProgramParameteri(ProgramID, GL_PROGRAM_BINARY_RETRIEVABLE_HINT, GL_TRUE);
         glLinkProgram(ProgramID);
@@ -1085,14 +1085,14 @@ void OpenGLHelper::debugMsgPrint(const int nType, const char *pFormat, ...)
     {
         OpenGLZone aZone;
 
-        if (GLEW_KHR_debug)
+        if (epoxy_has_gl_extension("GL_KHR_debug"))
             glDebugMessageInsert(GL_DEBUG_SOURCE_APPLICATION,
                                  GL_DEBUG_TYPE_OTHER,
                                  1, // one[sic] id is as good as another ?
                                  // GL_DEBUG_SEVERITY_NOTIFICATION for >= GL4.3 ?
                                  GL_DEBUG_SEVERITY_LOW,
                                  strlen(pStr), pStr);
-        else if (GLEW_AMD_debug_output)
+        else if (epoxy_has_gl_extension("GL_AMD_debug_output"))
             glDebugMessageInsertAMD(GL_DEBUG_CATEGORY_APPLICATION_AMD,
                                     GL_DEBUG_SEVERITY_LOW_AMD,
                                     1, // one[sic] id is as good as another ?