void
OceanSurfaceNode::rebuildShaders()
{
// need the terrain engine so we can get at the compositor.
TerrainEngineNode* engine = osgEarth::findTopMostNodeOfType<TerrainEngineNode>( this );
if ( !engine ) {
OE_DEBUG << LC << "No terrain engine found in the map node; abort" << std::endl;
return;
}
// access the compositor because we are going to be sampling map layers.
TextureCompositor* comp = engine->getTextureCompositor();
if ( !comp ) {
OE_INFO << LC << "No texture compositor found in the terrain engine; abort" << std::endl;
return;
}
// reserve a texture unit for the surface texture (if we haven't already)
if ( !_oceanSurfaceTextureApplied && _oceanSurfaceTextureUnit < 0 && _oceanSurfaceTexture.valid() )
{
if ( comp->reserveTextureImageUnit( _oceanSurfaceTextureUnit ) )
{
getOrCreateStateSet()->setTextureAttributeAndModes(
_oceanSurfaceTextureUnit, _oceanSurfaceTexture.get(), osg::StateAttribute::ON);
_oceanSurfaceTextureApplied = true;
}
else
{
OE_WARN << LC << "Sorry, failed to allocate a texture image unit for the surface texture." << std::endl;
}
}
// create a VP to store our custom shader components.
osgEarth::VirtualProgram* vp = new osgEarth::VirtualProgram();
getOrCreateStateSet()->setAttributeAndModes( vp, osg::StateAttribute::ON );
// if the ocean is disabled, just return without injecting any shaders.
if ( !_enabled )
return;
// build the sampler function if necessary
osg::ref_ptr<const ImageLayer> safeMaskLayer = _maskLayer.get();
osg::Shader* maskSampler = 0L;
if ( safeMaskLayer.valid() )
{
maskSampler = comp->createSamplerFunction( safeMaskLayer->getUID(), MASK_SAMPLER_FUNC, osg::Shader::VERTEX );
if ( maskSampler )
vp->setShader( MASK_SAMPLER_FUNC, maskSampler );
}
// make the helper functions.
{
std::stringstream buf;
buf << "vec3 xyz_to_lat_lon_height(in vec3 xyz) \n"
<< "{ \n"
<< " float X = xyz.x;\n"
<< " float Y = xyz.y;\n"
<< " float Z = xyz.z;\n"
<< " float _radiusEquator = 6378137.0;\n"
<< " float _radiusPolar = 6356752.3142;\n"
<< " float flattening = (_radiusEquator-_radiusPolar)/_radiusEquator;\n"
<< " float _eccentricitySquared = 2.0*flattening - flattening*flattening;\n"
<< " float p = sqrt(X*X + Y*Y);\n"
<< " float theta = atan(Z*_radiusEquator , (p*_radiusPolar));\n"
<< " float eDashSquared = (_radiusEquator*_radiusEquator - _radiusPolar*_radiusPolar)/(_radiusPolar*_radiusPolar);\n"
<< " float sin_theta = sin(theta);\n"
<< " float cos_theta = cos(theta);\n"
<< " float latitude = atan( (Z + eDashSquared*_radiusPolar*sin_theta*sin_theta*sin_theta), (p - _eccentricitySquared*_radiusEquator*cos_theta*cos_theta*cos_theta) );\n"
<< " float longitude = atan(Y,X);\n"
<< " float sin_latitude = sin(latitude);\n"
<< " float N = _radiusEquator / sqrt( 1.0 - _eccentricitySquared*sin_latitude*sin_latitude);\n"
<< " float height = p/cos(latitude) - N;\n"
<< " return vec3(longitude, latitude, height);\n"
<< "} \n"
<< "\n";
std::string str = buf.str();
vp->setShader( "xyz_to_lat_lon_height", new osg::Shader(osg::Shader::VERTEX, str) );
}
// next make the vertex shader function that will morph the ocean verts and prepare
// the texture coordinates for the surface effects.
{
std::stringstream buf;
buf << std::fixed;
buf << "uniform float osg_SimulationTime; \n"
<< "uniform mat4 osg_ViewMatrixInverse;\n"
<< "uniform mat4 osg_ViewMatrix;\n"
<< "uniform float osgearth_OceanHeight;\n"
<< "uniform float osgearth_OceanPeriod;\n"
<< "uniform float osgearth_OceanAnimationPeriod;\n"
<< "varying float osgearth_OceanAlpha;\n"
<< "varying float osgearth_CameraRange; \n"
<< "vec3 xyz_to_lat_lon_height(in vec3 xyz); \n";
if ( _oceanSurfaceTextureApplied )
{
buf << "varying vec3 osgearth_oceanSurfaceTexCoord; \n";
}
if ( maskSampler )
{
buf << "vec4 " << MASK_SAMPLER_FUNC << "(); \n";
}
buf << "void osgearth_ocean_morphSurface() \n"
<< "{ \n"
<< " mat4 modelMatrix = osg_ViewMatrixInverse * gl_ModelViewMatrix; \n"
<< " vec4 vert = modelMatrix * gl_Vertex; \n"
<< " vec3 vert3 = vec3(vert.x, vert.y, vert.z); \n"
<< " vec3 latlon = xyz_to_lat_lon_height(vert3); \n"
<< " osgearth_OceanAlpha = 1.0; \n";
if ( maskSampler )
{
buf << " osgearth_OceanAlpha = 1.0 - (" << MASK_SAMPLER_FUNC << "()).a; \n";
}
if ( _invertMask )
buf << " osgearth_OceanAlpha = 1.0 - osgearth_OceanAlpha; \n";
buf << " if ( osgearth_CameraRange <= " << _maxRange << " ) \n"
<< " { \n"
<< " float s = mix(1.0, 0.0, osgearth_CameraRange / " << _maxRange << "); \n" //Invert so it's between 0 and 1
<< " osgearth_OceanAlpha *= s; \n"
<< " } \n"
<< " else \n"
<< " { \n"
<< " osgearth_OceanAlpha = 0.0; \n"
<< " } \n"
<< " if (osgearth_OceanAlpha > 0.0) \n"
<< " { \n"
<< " float PI_2 = 3.14158 * 2.0; \n"
<< " float period = PI_2/osgearth_OceanPeriod; \n"
<< " float half_period = period / 2.0; \n"
<< " vec3 n = normalize(vert3);\n"
<< " float theta = (mod(latlon.x, period) / period) * PI_2; \n"
<< " float phi = (mod(latlon.y, half_period) / half_period) * PI_2; \n"
<< " float phase1 = osg_SimulationTime * 2.0; \n"
<< " float phase2 = osg_SimulationTime * 4.0; \n"
<< " float waveHeight = (osgearth_OceanAlpha) * osgearth_OceanHeight; \n"
<< " float scale1 = sin(theta + phase1) * waveHeight; \n"
<< " float scale2 = cos(phi + phase2) * waveHeight; \n"
<< " float scale3 = sin(theta + phase2) * cos(phi + phase1) * waveHeight * 1.6; \n"
<< " float scale = (scale1 + scale2 + scale3)/3.0; \n";
// flatten verts to MSL:
if ( _adjustToMSL )
{
buf << " vec3 offset = n * -latlon.z; \n"
<< " vert += vec4( offset.xyz, 0 ); \n";
}
// apply the save scale:
buf << " n = n * scale; \n"
<< " vert += vec4(n.x, n.y,n.z,0); \n"
<< " vert = osg_ViewMatrix * vert; \n"
<< " gl_Position = gl_ProjectionMatrix * vert; \n"
<< " }\n";
// set up the coords for the surface texture:
if ( _oceanSurfaceTextureApplied )
{
buf << " osgearth_oceanSurfaceTexCoord.x = latlon.x / " << _oceanSurfaceImageSizeRadians << "; \n"
<< " osgearth_oceanSurfaceTexCoord.y = latlon.y / " << _oceanSurfaceImageSizeRadians << "; \n"
<< " osgearth_oceanSurfaceTexCoord.z = fract(osg_SimulationTime/osgearth_OceanAnimationPeriod); \n";
}
buf << "}\n";
// add as a custom user function in the shader composition:
std::string vertSource = buf.str();
vp->setFunction( "osgearth_ocean_morphSurface", vertSource, osgEarth::ShaderComp::LOCATION_VERTEX_PRE_TEXTURING );
}
// now we need a fragment function that will apply the ocean surface texture.
if ( _oceanSurfaceTextureApplied )
{
getOrCreateStateSet()->getOrCreateUniform( "osgearth_oceanSurfaceTex", osg::Uniform::SAMPLER_3D )->set( _oceanSurfaceTextureUnit );
std::stringstream buf;
buf << "uniform sampler3D osgearth_oceanSurfaceTex; \n"
<< "varying vec3 osgearth_oceanSurfaceTexCoord; \n"
<< "varying float osgearth_OceanAlpha; \n"
<< "void osgearth_ocean_applySurfaceTex( inout vec4 color ) \n"
<< "{ \n"
<< " vec4 texel = texture3D(osgearth_oceanSurfaceTex, osgearth_oceanSurfaceTexCoord); \n"
<< " color = vec4( mix( color.rgb, texel.rgb, texel.a * osgearth_OceanAlpha ), color.a); \n"
<< "} \n";
std::string str = buf.str();
vp->setFunction( "osgearth_ocean_applySurfaceTex", str, osgEarth::ShaderComp::LOCATION_FRAGMENT_PRE_LIGHTING );
}
}
bool
ShadowUtils::setUpShadows(osgShadow::ShadowedScene* sscene, osg::Group* root)
{
osg::StateSet* ssStateSet = sscene->getOrCreateStateSet();
MapNode* mapNode = MapNode::findMapNode(root);
TerrainEngineNode* engine = mapNode->getTerrainEngine();
if (!engine)
return false;
TextureCompositor* compositor = engine->getTextureCompositor();
int su = -1;
if (!compositor->reserveTextureImageUnit(su))
return false;
OE_INFO << LC << "Reserved texture unit " << su << " for shadowing" << std::endl;
osgShadow::ViewDependentShadowMap* vdsm = dynamic_cast< osgShadow::ViewDependentShadowMap*>(sscene->getShadowTechnique());
int su1 = -1;
if (vdsm && sscene->getShadowSettings()->getNumShadowMapsPerLight() == 2)
{
if (!compositor->reserveTextureImageUnit(su1) || su1 != su + 1)
{
OE_FATAL << LC << "couldn't get contiguous shadows for split vdsm\n";
sscene->getShadowSettings()->setNumShadowMapsPerLight(1);
if (su1 != -1)
compositor->releaseTextureImageUnit(su1);
su1 = -1;
}
else
{
OE_INFO << LC << "Reserved texture unit " << su1 << " for shadowing" << std::endl;
}
}
// create a virtual program to attach to the shadowed scene.
VirtualProgram* vp = new VirtualProgram();
vp->setName( "shadow:terrain" );
//vp->installDefaultColoringAndLightingShaders();
ssStateSet->setAttributeAndModes( vp, 1 );
std::stringstream buf;
buf << "#version " << GLSL_VERSION_STR << "\n";
#ifdef OSG_GLES2_AVAILABLE
buf << "precision mediump float;\n";
#endif
buf << "varying vec4 oe_shadow_ambient;\n";
buf << "varying vec4 oe_shadow_TexCoord0;\n";
if ( su1 >= 0 )
buf << "varying vec4 oe_shadow_TexCoord1;\n";
buf << "void oe_shadow_setupShadowCoords(inout vec4 VertexVIEW)\n";
buf << "{\n";
buf << " vec4 position4 = VertexVIEW;\n";
buf << " oe_shadow_TexCoord0.s = dot( position4, gl_EyePlaneS[" << su <<"]);\n";
buf << " oe_shadow_TexCoord0.t = dot( position4, gl_EyePlaneT[" << su <<"]);\n";
buf << " oe_shadow_TexCoord0.p = dot( position4, gl_EyePlaneR[" << su <<"]);\n";
buf << " oe_shadow_TexCoord0.q = dot( position4, gl_EyePlaneQ[" << su <<"]);\n";
if (su1 >= 0)
{
buf << " oe_shadow_TexCoord1.s = dot( position4, gl_EyePlaneS[" << su1 <<"]);\n";
buf << " oe_shadow_TexCoord1.t = dot( position4, gl_EyePlaneT[" << su1 <<"]);\n";
buf << " oe_shadow_TexCoord1.p = dot( position4, gl_EyePlaneR[" << su1 <<"]);\n";
buf << " oe_shadow_TexCoord1.q = dot( position4, gl_EyePlaneQ[" << su1 <<"]);\n";
}
// the ambient lighting will control the intensity of the shadow.
buf << " oe_shadow_ambient = gl_FrontLightProduct[0].ambient; \n"
<< "}\n";
std::string setupShadowCoords;
setupShadowCoords = buf.str();
vp->setFunction(
"oe_shadow_setupShadowCoords",
setupShadowCoords,
ShaderComp::LOCATION_VERTEX_VIEW,
-1.0 );
std::stringstream buf2;
buf2 <<
"#version " << GLSL_VERSION_STR << "\n"
#ifdef OSG_GLES2_AVAILABLE
"precision mediump float;\n"
#endif
"uniform sampler2DShadow shadowTexture;\n"
"varying vec4 oe_shadow_TexCoord0;\n";
if (su1 >= 0)
{
// bound by vdsm
buf2 << "uniform sampler2DShadow shadowTexture1;\n";
buf2 << "varying vec4 oe_shadow_TexCoord1;\n";
}
buf2 <<
"varying vec4 oe_shadow_ambient;\n"
"void oe_shadow_applyLighting( inout vec4 color )\n"
"{\n"
" float alpha = color.a;\n"
" float shadowFac = shadow2DProj( shadowTexture, oe_shadow_TexCoord0).r;\n";
if (su1 > 0)
{
buf2 << " shadowFac *= shadow2DProj( shadowTexture1, oe_shadow_TexCoord1).r;\n";
}
// calculate the shadowed color and mix if with the lit color based on the
// ambient lighting. The 0.5 is a multiplier that darkens the shadow in
// proportion to ambient light. It should probably be a uniform.
buf2 <<
" vec4 colorInFullShadow = color * oe_shadow_ambient; \n"
" color = mix(colorInFullShadow, color, shadowFac); \n"
" color.a = alpha;\n"
"}\n";
std::string fragApplyLighting;
fragApplyLighting = buf2.str();
vp->setFunction(
"oe_shadow_applyLighting",
fragApplyLighting,
osgEarth::ShaderComp::LOCATION_FRAGMENT_LIGHTING );
setShadowUnit(sscene, su);
// VDSM uses a different sampler name, shadowTexture0.
ssStateSet
->getOrCreateUniform("shadowTexture", osg::Uniform::SAMPLER_2D_SHADOW)
->set(su);
return true;
}