From 1a3675956e500796e1652ac0518c30b967ffeae8 Mon Sep 17 00:00:00 2001
From: Matthias Koefferlein <matthias@koefferlein.de>
Date: Sat, 23 Jan 2021 15:54:02 +0100
Subject: [PATCH] Ported to OpenGL 3.2 for Windows compatibility.

---
 .../view_25d/lay_plugin/layD25ViewWidget.cc   | 32 ++++++++-----------
 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc b/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc
index 9d3c2ac41..4aaed12f1 100644
--- a/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc
@@ -195,9 +195,6 @@ D25ViewWidget::D25ViewWidget (QWidget *parent)
   format.setDepthBufferSize (24);
   format.setSamples (4); //  more -> widget extends beyond boundary!
   format.setStencilBufferSize (8);
-  format.setProfile (QSurfaceFormat::CoreProfile);
-  format.setVersion(3, 2);
-  format.setRenderableType (QSurfaceFormat::OpenGLES);
   setFormat (format);
 
   m_zmin = m_zmax = 0.0;
@@ -738,16 +735,16 @@ D25ViewWidget::do_initialize_gl ()
   glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
   static const char *shapes_vertex_shader_source =
-      "#version 320 es\n"
+      "#version 150\n"
       "\n"
-      "layout (location = 0) in vec4 posAttr;\n"
+      "in vec4 posAttr;\n"
       "\n"
       "void main() {\n"
       "   gl_Position = posAttr;\n"
       "}\n";
 
   static const char *shapes_geometry_shader_source =
-      "#version 320 es\n"
+      "#version 150\n"
       "\n"
       "uniform vec4 color;\n"
       "uniform vec4 ambient;\n"
@@ -775,7 +772,7 @@ D25ViewWidget::do_initialize_gl ()
       "}\n";
 
   static const char *shapes_fragment_shader_source =
-      "#version 320 es\n"
+      "#version 150\n"
       "\n"
       "in lowp vec4 vertexColor;\n"
       "out lowp vec4 fragColor;\n"
@@ -817,11 +814,9 @@ D25ViewWidget::do_initialize_gl ()
   //  grid plane shader source
 
   static const char *gridplan_vertex_shader_source =
-      "#version 320 es\n"
-      "#undef lowp\n"
-      "#undef highp\n"
-      "#undef mediump\n"
-      "layout (location = 0) in vec4 posAttr;\n"
+      "#version 150\n"
+      "\n"
+      "in vec4 posAttr;\n"
       "uniform mat4 matrix;\n"
       "\n"
       "void main() {\n"
@@ -829,10 +824,8 @@ D25ViewWidget::do_initialize_gl ()
       "}\n";
 
   static const char *gridplan_fragment_shader_source =
-      "#version 320 es\n"
-      "#undef lowp\n"
-      "#undef highp\n"
-      "#undef mediump\n"
+      "#version 150\n"
+      "\n"
       "uniform lowp vec4 color;\n"
       "out lowp vec4 fragColor;\n"
       "void main() {\n"
@@ -865,12 +858,12 @@ D25ViewWidget::paintGL ()
   glClearColor (float (c.red ()) / 255.0f, float (c.green ()) / 255.0f, float (c.blue ()) / 255.0f, 1.0);
   glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-  const int positions = 0;
-
   if (! m_shapes_program || ! m_gridplane_program) {
     return;
   }
 
+  int positions = m_shapes_program->attributeLocation ("posAttr");
+
   QMatrix4x4 scene_trans, scene_trans_wo_y;
 
   //  provide the displacement and scaling (in this order!)
@@ -907,8 +900,11 @@ D25ViewWidget::paintGL ()
 
   m_shapes_program->release ();
 
+
   //  decoration
 
+  positions = m_gridplane_program->attributeLocation ("posAttr");
+
   //  a vertex buffer for the decoration
   lay::mem_chunks<float, 1024 * 18> vertexes;