0025282: Visualization, OpenGl_PrimitiveArray - provide built-in GLSL programs as alternative to FFP

Enumerations Visual3d_TypeOfModel, V3d_TypeOfShadingModel.
- Remove unused values V3d_MULTICOLOR, V3d_HIDDEN, Visual3d_TOM_INTERP_COLOR.
- Add per-pixel shading mode - V3d_PHONG, Visual3d_TOM_FRAGMENT.

Draw Harness command vrenderparams.
Add option -shadingModel to setup Shading Model.

OpenGl_Caps::ffpEnable - new option to switch FFP/built-in GLSL programs.
OpenGl_ShaderManager - add built-in GLSL programs.

Draw Harness command vcaps.
- Fix command syntax to meet coding rules.
- Add option -ffp to activate/disable built-in GLSL programs.

GLSL API changes.
- Rename vertex attribute occColor -> occVertColor.
- Introduce vec4 occColor uniform variable for light-less shaders.
- Introduce float occPointSize uniform variable for marker programs.

OpenGl_VertexBuffer::bindAttribute() - activate normalization for non-GL_FLOAT types,
since color attribute is defined as 32-bit vector of 4 unsigned byte values.

OpenGl_Context - add methods SetColor4fv() and SetPointSize()
for parameters redirection to active GLSL program
(as alternative to glColor4fv() and glPointSize()).

OpenGl_ShaderProgram - define default precision for float types
in Fragment Shader within OpenGL ES 2.0+ context.

OpenGl_AspectMarker, initialize Aspect_TOM_O_POINT display list
in the same way as sprite texture.

OpenGl_Texture, do not use sized internal formats on OpenGL ES.

src/OpenGl/OpenGl_View.hxx

@@ -36,6 +36,7 @@
 #include <Graphic3d_SequenceOfHClipPlane.hxx>
 #include <Graphic3d_ZLayerSettings.hxx>
 #include <Visual3d_TypeOfSurfaceDetail.hxx>
+#include <Visual3d_TypeOfModel.hxx>
 
 #include <OpenGl_BVHTreeSelector.hxx>
 #include <OpenGl_LayerList.hxx>
@@ -257,7 +258,7 @@ protected:
 
   //View_LABViewContext
   int myVisualization;
-  int myIntShadingMethod;
+  Visual3d_TypeOfModel       myShadingModel;  //!< lighting shading model
 
   //View_LABLight
   OpenGl_ListOfLight myLights;