osg shader动态线实现代码 及应用

A：以下是osg shader动态线的实现代码及应用示例：

实现代码：

uniform float lineWidth;
uniform vec4 lineColor;

void main()
{
    gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
    gl_PointSize = max(1.0, lineWidth / gl_Position.w);
    gl_FrontColor = lineColor;
}

应用示例：

// 定义动态线的线宽和颜色
osg::ref_ptr<osg::Uniform> lineWidthUniform = new osg::Uniform("lineWidth", float(5.0));
osg::ref_ptr<osg::Uniform> lineColorUniform = new osg::Uniform("lineColor", osg::Vec4(1.0, 0.0, 0.0, 1.0));

// 创建动态线节点
osg::ref_ptr<osg::Program> lineProgram = new osg::Program;
osg::ref_ptr<osg::Shader> lineVertexShader = new osg::Shader(osg::Shader::VERTEX, lineVertexShaderSource);
osg::ref_ptr<osg::Shader> lineFragmentShader = new osg::Shader(osg::Shader::FRAGMENT, lineFragmentShaderSource);
lineProgram->addShader(lineVertexShader.get());
lineProgram->addShader(lineFragmentShader.get());

osg::ref_ptr<osg::Geometry> lineGeom = new osg::Geometry;
lineGeom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::LINE_STRIP, 0, linePoints->size()));
lineGeom->setVertexArray(lineVertexes.get());
lineGeom->setTexCoordArray(0, lineTexCoords.get());
lineGeom->setProgram(lineProgram.get());
lineGeom->getOrCreateStateSet()->addUniform(lineWidthUniform.get());
lineGeom->getOrCreateStateSet()->addUniform(lineColorUniform.get());

osg::ref_ptr<osg::Geode> lineGeode = new osg::Geode;
lineGeode->addDrawable(lineGeom.get());

// 将动态线节点添加到场景图中
osg::ref_ptr<osg::Group> root = new osg::Group;
root->addChild(lineGeode.get());