OpenSceneGraph/examples/osgoit/HeatMap.cpp

233 lines
8.6 KiB
C++

/*
* 3D Heat map using vertex displacement mapping
* Rendered using depth peeling in fragment shader.
*/
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/Vec3>
#include <osg/MatrixTransform>
#include <osg/PositionAttitudeTransform>
#include <osg/LightModel>
#include <osg/io_utils>
#include <osg/Material>
#include <osgDB/ReadFile>
#include <osgDB/WriteFile>
#include <osgGA/TrackballManipulator>
#include <osgViewer/Viewer>
#include <osg/Math>
#include <iostream>
#define _USE_MATH_DEFINES
#include <math.h>
#include <osg/TexEnv>
#include <osg/TexMat>
#include <osg/Depth>
#include <osg/ShapeDrawable>
#include <osg/Texture1D>
#include <osg/Texture2D>
#include <osg/PolygonMode>
#include <osg/PolygonOffset>
#include "HeatMap.h"
#include "DepthPeeling.h"
///////////////////////////////////////////////////////////////////////////
// in-line GLSL source code
static const char *VertexShader = {
"#version 120\n"
"uniform float maximum;\n"
"uniform float maxheight;\n"
"uniform float transparency;\n"
"uniform sampler1D colortex;\n"
"uniform sampler2D datatex;\n"
"in vec2 xypos;\n"
"void main(void)\n"
"{\n"
" float foo;\n"
" float tmp = min(texture2D(datatex, xypos).x / maximum, 1.0);\n"
" gl_Position = gl_ModelViewProjectionMatrix * (gl_Vertex + vec4(0.0, 0.0, maxheight * tmp, 0.0));\n"
" vec4 color = texture1D(colortex, tmp);\n"
" color.w = color.w * transparency;\n"
" gl_FrontColor = color;\n"
" gl_BackColor = color;\n"
"}\n"
};
static const char *FragmentShader =
{
"#version 120\n"
"bool depthpeeling();\n"
"void main(void)\n"
"{\n"
" if( depthpeeling() ) discard;\n"
" gl_FragColor = gl_Color;\n"
"}\n"
};
/**
* Overloaded Geometry class to return predefined bounds
*/
class MyGeometry : public osg::Geometry
{
public:
MyGeometry(osg::BoundingBox bounds)
{
m_bounds = bounds;
m_bsphere = osg::BoundingSphere(bounds);
}
// an attempt to return a reasonable bounding box. Still does not prevent clipping of the heat map.
virtual const osg::BoundingBox& getBoundingBox() const {return m_bounds;}
virtual osg::BoundingBox computeBound() const {return m_bounds;}
virtual const osg::BoundingSphere& getBound() const {return m_bsphere;}
protected:
osg::BoundingBox m_bounds;
osg::BoundingSphere m_bsphere;
};
Heatmap::Heatmap(float width, float depth, float maxheight, unsigned int K, unsigned int N, float maximum, float transparency)
{
m_K = K;
m_N = N;
const int O = 4;
// create Geometry object to store all the vertices primitives.
osg::Geometry *meshGeom = new MyGeometry(osg::BoundingBox(osg::Vec3(-width/2, -depth/2, 0), osg::Vec3(width/2, depth/2, maxheight)));
// we use a float attribute array storing texcoords
osg::Vec2Array* xypositions = new osg::Vec2Array();
xypositions->setName("xypos");
// create vertex coordinates
osg::Vec3Array* vertices = new osg::Vec3Array();
osg::Vec3 off(-width/2, -depth/2, 0);
for (unsigned int y=0; y < O*N; y++) {
if (y % 2 == 0)
{
for (unsigned int x=0; x < O*K; x++) {
vertices->push_back(osg::Vec3(width*x/(O*K-1), depth*y/(O*N-1), 0.0)+off);
xypositions->push_back(osg::Vec2(((float)x+0.5f)/(O*K),((float)y+0.5f)/(O*N)));
}
}
else
{
vertices->push_back(osg::Vec3(0, depth*y/(O*N-1), 0.0)+off);
xypositions->push_back(osg::Vec2(0.5f/(O*K),((float)y+0.5f)/(O*N)));
for (unsigned int x=0; x < O*K-1; x++) {
vertices->push_back(osg::Vec3(width*(0.5+x)/(O*K-1), depth*y/(O*N-1), 0.0)+off);
xypositions->push_back(osg::Vec2(((float)(x+0.5f)+0.5f)/(O*K),((float)y+0.5f)/(O*N)));
}
vertices->push_back(osg::Vec3(width, depth*y/(O*N-1), 0.0)+off);
xypositions->push_back(osg::Vec2(1.0f-0.5f/(O*K),((float)y+0.5f)/(O*N)));
}
}
xypositions->setBinding(osg::Array::BIND_PER_VERTEX);
xypositions->setNormalize(false);
meshGeom->setVertexAttribArray(6, xypositions);
meshGeom->setVertexArray(vertices);
// generate several tri strips to form a mesh
GLuint *indices = new GLuint[4*O*K];
for (unsigned int y=0; y < O*N-1; y++) {
if (y % 2 == 0)
{
int base = (y/2) * (O*K+O*K+1);
int base2 = (y/2) * (O*K+O*K+1) + O*K;
int i=0; for (unsigned int x=0; x < O*K; x++) { indices[i++] = base2+x; indices[i++] = base+x;}
indices[i++] = base2+O*K;
meshGeom->addPrimitiveSet(new osg::DrawElementsUInt(osg::PrimitiveSet::TRIANGLE_STRIP, i, indices));
}
else
{
int base = (y/2) * (O*K+O*K+1) + O*K;
int base2 = (y/2) * (O*K+O*K+1) + O*K + O*K+1;
int i=0; for (unsigned int x=0; x < O*K; x++) { indices[i++] = base+x; indices[i++] = base2+x;}
indices[i++] = base+O*K;
meshGeom->addPrimitiveSet(new osg::DrawElementsUInt(osg::PrimitiveSet::TRIANGLE_STRIP, i, indices));
}
}
delete[] indices;
// create vertex and fragment shader
osg::Program* program = new osg::Program;
program->setName( "mesh" );
program->addBindAttribLocation("xypos", 6);
program->addShader( new osg::Shader( osg::Shader::VERTEX, VertexShader ) );
program->addShader( new osg::Shader( osg::Shader::FRAGMENT, DepthPeeling::PeelingShader ) );
program->addShader( new osg::Shader( osg::Shader::FRAGMENT, FragmentShader ) );
// create a 1D texture for color lookups
colorimg = new osg::Image();
colorimg->allocateImage(5, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE);
unsigned char *data = colorimg->data();
*data++ = 0; *data++ = 0; *data++ = 255; *data++ = 0; // fully transparent blue
*data++ = 0; *data++ = 255; *data++ = 255; *data++ = 255; // turquoise
*data++ = 0; *data++ = 255; *data++ = 0; *data++ = 255; // green
*data++ = 255; *data++ = 255; *data++ = 0; *data++ = 255; // yellow
*data++ = 255; *data++ = 0; *data++ = 0; *data++ = 255; // red
colortex = new osg::Texture1D(colorimg.get());
colortex->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
colortex->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
colortex->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
colortex->setResizeNonPowerOfTwoHint(false);
// create a 2D texture for data lookups
m_img2 = new osg::Image();
m_img2->allocateImage(K, N, 1, GL_LUMINANCE, GL_FLOAT);
m_img2->setInternalTextureFormat(GL_RGB32F_ARB);
m_data = (float*)m_img2.get()->data();
m_tex2 = new osg::Texture2D(m_img2.get());
m_tex2.get()->setResizeNonPowerOfTwoHint(false);
m_tex2.get()->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
m_tex2.get()->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
m_tex2.get()->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
m_tex2.get()->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
// set render states
osg::StateSet *meshstate = meshGeom->getOrCreateStateSet();
meshstate->setMode(GL_BLEND, osg::StateAttribute::ON);
meshstate->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
meshstate->setAttributeAndModes(program, osg::StateAttribute::ON);
meshstate->setTextureAttributeAndModes(0,colortex.get(),osg::StateAttribute::ON);
meshstate->setTextureAttributeAndModes(1,m_tex2.get(),osg::StateAttribute::ON);
// uniforms for height and color scaling
maximumUniform = new osg::Uniform( "maximum", (float)maximum );
maxheightUniform = new osg::Uniform( "maxheight", (float)maxheight );
transparencyUniform = new osg::Uniform( "transparency", (float)transparency);
osg::Uniform* texUniform = new osg::Uniform(osg::Uniform::SAMPLER_1D, "colortex");
texUniform->set(0);
osg::Uniform* texUniform2 = new osg::Uniform(osg::Uniform::SAMPLER_2D, "datatex");
texUniform2->set(1);
meshstate->addUniform(texUniform);
meshstate->addUniform(texUniform2);
meshstate->addUniform(maximumUniform);
meshstate->addUniform(maxheightUniform);
meshstate->addUniform(transparencyUniform);
// add the geometries to the geode.
meshGeom->setUseDisplayList(false);
addDrawable(meshGeom);
}
void Heatmap::setData(float *buffer, float maxheight, float maximum, float transparency)
{
memcpy(m_data, buffer, m_N*m_K*sizeof(float));
maximumUniform->set( maximum );
maxheightUniform->set( maxheight );
transparencyUniform->set ( transparency );
m_img2.get()->dirty();
}
Heatmap::~Heatmap()
{
}