OpenSceneGraph/examples/osgshaderterrain/osgshaderterrain.cpp

332 lines
10 KiB
C++

/* OpenSceneGraph example, osgshaderterrain.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <osg/AlphaFunc>
#include <osg/Billboard>
#include <osg/BlendFunc>
#include <osg/Depth>
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/GLExtensions>
#include <osg/Material>
#include <osg/Math>
#include <osg/MatrixTransform>
#include <osg/PolygonOffset>
#include <osg/Program>
#include <osg/Projection>
#include <osg/Shader>
#include <osg/ShapeDrawable>
#include <osg/StateSet>
#include <osg/Switch>
#include <osg/Texture2D>
#include <osg/Uniform>
#include <osgDB/ReadFile>
#include <osgDB/FileUtils>
#include <osgUtil/SmoothingVisitor>
#include <osgText/Text>
#include <osgViewer/Viewer>
#include <iostream>
// for the grid data..
#include "../osghangglide/terrain_coords.h"
osg::Node* createScene()
{
osg::Group* scene = new osg::Group;
unsigned int numColumns = 38;
unsigned int numRows = 39;
unsigned int r;
unsigned int c;
osg::Vec3 origin(0.0f,0.0f,0.0f);
osg::Vec3 size(1000.0f,1000.0f,250.0f);
osg::Vec3 scaleDown(1.0f/size.x(),1.0f/size.y(),1.0f/size.z());
// ---------------------------------------
// Set up a StateSet to texture the objects
// ---------------------------------------
osg::StateSet* stateset = new osg::StateSet();
osg::Uniform* originUniform = new osg::Uniform("terrainOrigin",origin);
stateset->addUniform(originUniform);
osg::Uniform* sizeUniform = new osg::Uniform("terrainSize",size);
stateset->addUniform(sizeUniform);
osg::Uniform* scaleDownUniform = new osg::Uniform("terrainScaleDown",scaleDown);
stateset->addUniform(scaleDownUniform);
osg::Uniform* terrainTextureSampler = new osg::Uniform("terrainTexture",0);
stateset->addUniform(terrainTextureSampler);
osg::Uniform* baseTextureSampler = new osg::Uniform("baseTexture",1);
stateset->addUniform(baseTextureSampler);
osg::Uniform* treeTextureSampler = new osg::Uniform("treeTexture",1);
stateset->addUniform(treeTextureSampler);
// compute z range of z values of grid data so we can scale it.
float min_z = FLT_MAX;
float max_z = -FLT_MAX;
for(r=0;r<numRows;++r)
{
for(c=0;c<numColumns;++c)
{
min_z = osg::minimum(min_z,vertex[r+c*numRows][2]);
max_z = osg::maximum(max_z,vertex[r+c*numRows][2]);
}
}
float scale_z = size.z()/(max_z-min_z);
osg::Image* terrainImage = new osg::Image;
terrainImage->allocateImage(numColumns,numRows,1,GL_LUMINANCE, GL_FLOAT);
terrainImage->setInternalTextureFormat(GL_LUMINANCE_FLOAT32_ATI);
for(r=0;r<numRows;++r)
{
for(c=0;c<numColumns;++c)
{
*((float*)(terrainImage->data(c,r))) = (vertex[r+c*numRows][2]-min_z)*scale_z;
}
}
osg::Texture2D* terrainTexture = new osg::Texture2D;
terrainTexture->setImage(terrainImage);
terrainTexture->setFilter(osg::Texture2D::MIN_FILTER, osg::Texture2D::NEAREST);
terrainTexture->setFilter(osg::Texture2D::MAG_FILTER, osg::Texture2D::NEAREST);
terrainTexture->setResizeNonPowerOfTwoHint(false);
stateset->setTextureAttributeAndModes(0,terrainTexture,osg::StateAttribute::ON);
osg::ref_ptr<osg::Image> image = osgDB::readRefImageFile("Images/lz.rgb");
if (image)
{
osg::Texture2D* texture = new osg::Texture2D;
texture->setImage(image);
stateset->setTextureAttributeAndModes(1,texture,osg::StateAttribute::ON);
}
{
std::cout<<"Creating terrain...";
osg::Geode* geode = new osg::Geode();
geode->setStateSet( stateset );
{
osg::Program* program = new osg::Program;
stateset->setAttribute(program);
#if 1
// use inline shaders
///////////////////////////////////////////////////////////////////
// vertex shader using just Vec4 coefficients
char vertexShaderSource[] =
"uniform sampler2D terrainTexture;\n"
"uniform vec3 terrainOrigin;\n"
"uniform vec3 terrainScaleDown;\n"
"\n"
"varying vec2 texcoord;\n"
"\n"
"void main(void)\n"
"{\n"
" texcoord = gl_Vertex.xy - terrainOrigin.xy;\n"
" texcoord.x *= terrainScaleDown.x;\n"
" texcoord.y *= terrainScaleDown.y;\n"
"\n"
" vec4 position;\n"
" position.x = gl_Vertex.x;\n"
" position.y = gl_Vertex.y;\n"
" position.z = texture2D(terrainTexture, texcoord).r;\n"
" position.w = 1.0;\n"
" \n"
" gl_Position = gl_ModelViewProjectionMatrix * position;\n"
" gl_FrontColor = vec4(1.0,1.0,1.0,1.0);\n"
"}\n";
//////////////////////////////////////////////////////////////////
// fragment shader
//
char fragmentShaderSource[] =
"uniform sampler2D baseTexture; \n"
"varying vec2 texcoord;\n"
"\n"
"void main(void) \n"
"{\n"
" gl_FragColor = texture2D( baseTexture, texcoord); \n"
"}\n";
program->addShader(new osg::Shader(osg::Shader::VERTEX, vertexShaderSource));
program->addShader(new osg::Shader(osg::Shader::FRAGMENT, fragmentShaderSource));
#else
// get shaders from source
program->addShader(osg::Shader::readShaderFile(osg::Shader::VERTEX, osgDB::findDataFile("shaders/terrain.vert")));
program->addShader(osg::Shader::readShaderFile(osg::Shader::FRAGMENT, osgDB::findDataFile("shaders/terrain.frag")));
#endif
// get shaders from source
}
{
osg::Geometry* geometry = new osg::Geometry;
osg::Vec3Array& v = *(new osg::Vec3Array(numColumns*numRows));
osg::Vec4ubArray& color = *(new osg::Vec4ubArray(1));
color[0].set(255,255,255,255);
float rowCoordDelta = size.y()/(float)(numRows-1);
float columnCoordDelta = size.x()/(float)(numColumns-1);
float rowTexDelta = 1.0f/(float)(numRows-1);
float columnTexDelta = 1.0f/(float)(numColumns-1);
osg::Vec3 pos = origin;
osg::Vec2 tex(0.0f,0.0f);
int vi=0;
for(r=0;r<numRows;++r)
{
pos.x() = origin.x();
tex.x() = 0.0f;
for(c=0;c<numColumns;++c)
{
v[vi].set(pos.x(),pos.y(),pos.z());
pos.x()+=columnCoordDelta;
tex.x()+=columnTexDelta;
++vi;
}
pos.y() += rowCoordDelta;
tex.y() += rowTexDelta;
}
geometry->setVertexArray(&v);
geometry->setColorArray(&color, osg::Array::BIND_OVERALL);
for(r=0;r<numRows-1;++r)
{
osg::DrawElementsUShort& drawElements = *(new osg::DrawElementsUShort(GL_QUAD_STRIP,2*numColumns));
geometry->addPrimitiveSet(&drawElements);
int ei=0;
for(c=0;c<numColumns;++c)
{
drawElements[ei++] = (r+1)*numColumns+c;
drawElements[ei++] = (r)*numColumns+c;
}
}
geometry->setInitialBound(osg::BoundingBox(origin, origin+size));
geode->addDrawable(geometry);
scene->addChild(geode);
}
}
std::cout<<"done."<<std::endl;
return scene;
}
class TestSupportOperation: public osg::GraphicsOperation
{
public:
TestSupportOperation():
osg::Referenced(true),
osg::GraphicsOperation("TestSupportOperation",false),
_supported(true),
_errorMessage() {}
virtual void operator () (osg::GraphicsContext* gc)
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
osg::GLExtensions* gl2ext = gc->getState()->get<osg::GLExtensions>();
if( gl2ext )
{
if( !gl2ext->isGlslSupported )
{
_supported = false;
_errorMessage = "ERROR: GLSL not supported by OpenGL driver.";
}
GLint numVertexTexUnits = 0;
glGetIntegerv( GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS, &numVertexTexUnits );
if( numVertexTexUnits <= 0 )
{
_supported = false;
_errorMessage = "ERROR: vertex texturing not supported by OpenGL driver.";
}
}
else
{
_supported = false;
_errorMessage = "ERROR: GLSL not supported.";
}
}
OpenThreads::Mutex _mutex;
bool _supported;
std::string _errorMessage;
};
int main(int, char **)
{
// construct the viewer.
osgViewer::Viewer viewer;
osg::Node* node = createScene();
// add model to viewer.
viewer.setSceneData( node );
viewer.setUpViewAcrossAllScreens();
osg::ref_ptr<TestSupportOperation> testSupportOperation = new TestSupportOperation;
#if 0
// temporarily commenting out as its causing the viewer to crash... no clue yet to why
viewer.setRealizeOperation(testSupportOperation.get());
#endif
// create the windows and run the threads.
viewer.realize();
if (!testSupportOperation->_supported)
{
osg::notify(osg::WARN)<<testSupportOperation->_errorMessage<<std::endl;
return 1;
}
return viewer.run();
}