Thanks, I managed to implement a standard bump mapping shader in OSG. Below is a code snippet that does it if it might help someone else. Shaders are attached.
Cheers,
Morne
osg::Node * VOSGFloorGrid::CreateBumpMappedFloor()
{
const int BASE_TEX_UNIT = 0;
const int BUMP_TEX_UNIT = 1;
const int TANGENT_ATR_UNIT = 6;
const int BINORMAL_ATR_UNIT = 7;
osg::Geode* geode = new osg::Geode;
// set up the Geometry.
osg::Geometry* geom = new osg::Geometry;
osg::Vec3 width, depth, topleft;
topleft = osg::Vec3( -Size/2.0, -Size/2.0, 0.0 );
width = osg::Vec3( Size, 0.0, 0.0 );
depth = osg::Vec3( 0.0, Size, 0.0 );
osg::Vec3Array* coords = new osg::Vec3Array(4);
(*coords)[0] = topleft;
(*coords)[1] = topleft+width;
(*coords)[2] = topleft+width+depth;
(*coords)[3] = topleft+depth;
geom->setVertexArray(coords);
osg::Vec3Array* norms = new osg::Vec3Array(1);
(*norms)[0] = osg::Vec3( 0.0, 1.0, 0.0 );
geom->setNormalArray(norms);
geom->setNormalBinding(osg::Geometry::BIND_OVERALL);
osg::Vec4Array* color = new osg::Vec4Array(1);
(*color)[0] = osg::Vec4(1.0f,1.0f,1.0f,1.0f);
geom->setColorArray( color );
geom->setColorBinding( osg::Geometry::BIND_OVERALL );
osg::Vec2Array* tcoords = new osg::Vec2Array(4);
float n = 5.0f; // no of times the texture is repeated
(*tcoords)[0].set( 0.0f, 0.0f );
(*tcoords)[1].set( n, 0.0f );
(*tcoords)[2].set( n, n );
(*tcoords)[3].set( 0.0f, n );
geom->setTexCoordArray( BASE_TEX_UNIT, tcoords );
geom->setTexCoordArray( BUMP_TEX_UNIT, tcoords );
geom->addPrimitiveSet( new osg::DrawArrays( osg::PrimitiveSet::QUADS, 0 ,
coords->size() ) );
geode->addDrawable( geom );
// Compute smoothed normals
osgUtil::SmoothingVisitor smoother;
smoother.apply( *geode );
// model texture
osg::Texture2D * diffuse = new osg::Texture2D;
diffuse->setImage( osgDB::readImageFile( m_sSystemPath +
"/Resources/Floor.tga" ) );
diffuse->setWrap( osg::Texture2D::WRAP_S, osg::Texture2D::REPEAT );
diffuse->setWrap( osg::Texture2D::WRAP_T, osg::Texture2D::REPEAT );
diffuse->setResizeNonPowerOfTwoHint( false );
diffuse->setMaxAnisotropy( 8.0f );
// bump map texture
osg::Texture2D * normal = new osg::Texture2D;
normal->setImage( osgDB::readImageFile( m_sSystemPath +
"/Resources/FloorNormalMap.tga" ) );
normal->setWrap( osg::Texture2D::WRAP_S, osg::Texture2D::REPEAT );
normal->setWrap( osg::Texture2D::WRAP_T, osg::Texture2D::REPEAT );
normal->setResizeNonPowerOfTwoHint( false );
normal->setMaxAnisotropy( 8.0f );
//////////////////////////////////////////////////////////////////////////
// Set up bump mapping shaders
// Load and compile shader source
osg::Program * bump = new osg::Program;
osg::Shader * bumpVertexShader = new osg::Shader( osg::Shader::VERTEX );
osg::Shader * bumpPixelShader = new osg::Shader( osg::Shader::FRAGMENT );
bumpVertexShader->loadShaderSourceFromFile( m_sSystemPath +
"/Resources/bumpmap.vert" );
bumpPixelShader->loadShaderSourceFromFile( m_sSystemPath +
"/Resources/bumpmap.frag" );
bump->addShader( bumpVertexShader );
bump->addShader( bumpPixelShader );
// Set up the shader stateset
osg::StateSet * stateset = geode->getOrCreateStateSet();
stateset->setTextureAttribute( BASE_TEX_UNIT, diffuse );
stateset->setTextureAttribute( BUMP_TEX_UNIT, normal );
stateset->setAttributeAndModes( bump, osg::StateAttribute::ON );
// Compute tangent space for geometry
osg::ref_ptr< osgUtil::TangentSpaceGenerator > tsg = new
osgUtil::TangentSpaceGenerator;
tsg->generate( geom, BUMP_TEX_UNIT );
geom->setVertexAttribData( TANGENT_ATR_UNIT, osg::Geometry::ArrayData(
tsg->getTangentArray(), osg::Geometry::BIND_PER_VERTEX, GL_FALSE ) );
geom->setVertexAttribData( BINORMAL_ATR_UNIT, osg::Geometry::ArrayData(
tsg->getBinormalArray(), osg::Geometry::BIND_PER_VERTEX, GL_FALSE ) );
bump->addBindAttribLocation( "rm_Tangent", TANGENT_ATR_UNIT );
bump->addBindAttribLocation( "rm_Binormal", BINORMAL_ATR_UNIT );
// Initialise Uniforms
// Vertex shader
osg::Vec3 Pos( 0, 0, 1000 );
stateset->addUniform( new osg::Uniform( "fvLightPosition", Pos ) );
stateset->addUniform( new osg::Uniform( "fvEyePosition", Pos ) );
stateset->addUniform( new osg::Uniform( "bumpMap", BUMP_TEX_UNIT ) );
stateset->addUniform( new osg::Uniform( "bumpMap", BUMP_TEX_UNIT ) );
// Fragment shader
stateset->addUniform( new osg::Uniform( "fvAmbient", osg::Vec4( 0.36,
0.36, 0.36, 1.0 ) ) );
stateset->addUniform( new osg::Uniform( "fvSpecular", osg::Vec4( 0.49,
0.49, 0.49, 1.0 ) ) );
stateset->addUniform( new osg::Uniform( "fvDiffuse", osg::Vec4( 0.88,
0.88, 0.88, 1.0 ) ) );
stateset->addUniform( new osg::Uniform( "fSpecularPower", 100.0f ) );
return geode;
}
On Mon, Nov 24, 2008 at 5:02 PM, Alejandro Aguilar Sierra <
[EMAIL PROTECTED]> wrote:
> Hi,
>
> I suggest you to see the osgshaders example (how osg deals with glsl)
> and then consult chapter 11 of the orange book (OpenGL shading
> language). You can find the shaders used in the book at
> http://3dshaders.com/
>
> Hope it helps.
>
> -- A.
>
> On Mon, Nov 24, 2008 at 10:39 AM, Morné Pistorius
> <[EMAIL PROTECTED]> wrote:
> > Hi all,
> > I added bump mapping to a model using osgFX::BumpMapping, but I need
> > something more flexible. My model has two sided lighting and osgFX
> doesn't
> > support that. Do we have GLSL shaders for bumpmapping in OSG? I think
> that
> > would be easier to modify to suit my needs than the assembler coded
> shaders
> > used in osgFX. If anyone has an example of applying normal mapping with
> > shaders in OSG, I would greatly appreciate it.
> > Thank you kindly,
> > Morne
> > _______________________________________________
> > osg-users mailing list
> > [email protected]
> >
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> >
> >
> _______________________________________________
> osg-users mailing list
> [email protected]
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
>
bumpmap.frag
Description: Binary data
bumpmap.vert
Description: Binary data
_______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
