Method Earth

samples/Earthquake/src/Earth.cpp:20–59

using namespace ci::app;

Earth::Earth()
	: mLoc( 0 ), mRadius( 250 ), mMinMagToRender( 2 ), mNumQuakes( 0 )
{
	mLightDir = glm::normalize( vec3( 0.025f, 0.25f, 1.0f ) );

	// Load the textures for the Earth.
	auto fmt = gl::Texture2d::Format().wrap( GL_REPEAT ).mipmap().minFilter( GL_LINEAR_MIPMAP_LINEAR );
	mTexDiffuse = gl::Texture2d::create( loadImage( loadResource( RES_EARTHDIFFUSE ) ), fmt );
	mTexNormal = gl::Texture2d::create( loadImage( loadResource( RES_EARTHNORMAL ) ), fmt );
	mTexMask = gl::Texture2d::create( loadImage( loadResource( RES_EARTHMASK ) ), fmt );

	// Create the Earth mesh with a custom shader.
	auto earthShader = gl::GlslProg::create( loadResource( RES_PASSTHRU_VERT ), loadResource( RES_EARTH_FRAG ) );
	earthShader->uniform( "texDiffuse", 0 );
	earthShader->uniform( "texNormal", 1 );
	earthShader->uniform( "texMask", 2 );
	mEarth = gl::Batch::create( geom::Sphere().radius( mRadius ).subdivisions( 120 ), earthShader );

	// Create a cone mesh with a custom shader, which we use to visualize earthquakes.
	gl::VboMeshRef mesh = gl::VboMesh::create( geom::Cone().height( 1 ).ratio( 0.25f ).subdivisionsHeight( 6 ).subdivisionsAxis( 30 ) );

	// Create an array of initial per-instance model matrices.
	std::vector<mat4> transforms;
	transforms.resize( MAX_NUMBER_OF_QUAKES );

	// Create the VBO which will contain per-instance (rather than per-vertex) data.
	mInstanceDataVbo = gl::Vbo::create( GL_ARRAY_BUFFER, transforms.size() * sizeof( mat4 ), transforms.data(), GL_STATIC_DRAW );

	// We need a geom::BufferLayout to describe this data as mapping to the CUSTOM_0 semantic,
	// and the 1 (rather than 0) as the last param indicates per-instance (rather than per-vertex).
	geom::BufferLayout instanceDataLayout;
	instanceDataLayout.append( geom::Attrib::CUSTOM_0, 16, sizeof( mat4 ), 0, 1 /* per instance */ );

	// Now add it to the VboMesh we already made of the Cone.
	mesh->appendVbo( instanceDataLayout, mInstanceDataVbo );

	// And finally, build our batch, mapping our CUSTOM_0 attribute to the "iModelMatrix" GLSL vertex attribute.
	auto quakeShader = gl::GlslProg::create( loadResource( RES_QUAKE_VERT ), loadResource( RES_QUAKE_FRAG ) );
	mQuake = gl::Batch::create( mesh, quakeShader, { { geom::Attrib::CUSTOM_0, "iModelMatrix" } } );
}

void Earth::update()
{