OpenSpace/modules/kameleonvolume/rendering/kameleonvolumeraycaster.cpp

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 * OpenSpace                                                                             *
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 * Copyright (c) 2014-2016                                                               *
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#include <modules/kameleonvolume/rendering/kameleonvolumeraycaster.h>

#include <glm/glm.hpp>
#include <ghoul/opengl/ghoul_gl.h>
#include <sstream>
#include <ghoul/opengl/programobject.h>
#include <openspace/util/powerscaledcoordinate.h>
#include <openspace/util/updatestructures.h>
#include <openspace/rendering/renderable.h>
#include <modules/kameleonvolume/rendering/renderablekameleonvolume.h>


namespace {
    const std::string GlslRaycastPath = "${MODULES}/kameleonvolume/shaders/raycast.glsl";
    const std::string GlslHelperPath = "${MODULES}/kameleonvolume/shaders/helper.glsl";
    const std::string GlslBoundsVsPath = "${MODULES}/kameleonvolume/shaders/boundsvs.glsl";
    const std::string GlslBoundsFsPath = "${MODULES}/kameleonvolume/shaders/boundsfs.glsl";
}

namespace openspace {

KameleonVolumeRaycaster::KameleonVolumeRaycaster(
    std::shared_ptr<ghoul::opengl::Texture> texture,
    std::shared_ptr<TransferFunction> transferFunction)
    : _volumeTexture(texture)
    , _transferFunction(transferFunction)
    , _boundingBox(glm::vec3(1.0)) {}
    
KameleonVolumeRaycaster::~KameleonVolumeRaycaster() {}

void KameleonVolumeRaycaster::initialize() {
    _boundingBox.initialize();
}
    
void KameleonVolumeRaycaster::deinitialize() {
}
    
void KameleonVolumeRaycaster::renderEntryPoints(const RenderData& data, ghoul::opengl::ProgramObject& program) {
    //program.setUniform("modelTransform", _modelTransform);
    program.setUniform("viewProjection", data.camera.viewProjectionMatrix());
    Renderable::setPscUniforms(program, data.camera, data.position);
    
    // Cull back face
    glEnable(GL_CULL_FACE);
    glCullFace(GL_BACK);
    
    // Render bounding geometry
    _boundingBox.render();
}
    
void KameleonVolumeRaycaster::renderExitPoints(const RenderData& data, ghoul::opengl::ProgramObject& program) {   
    // Uniforms
    //program.setUniform("modelTransform", _modelTransform);
    program.setUniform("viewProjection", data.camera.viewProjectionMatrix());
    Renderable::setPscUniforms(program, data.camera, data.position);

    // Cull front face
    glEnable(GL_CULL_FACE);
    glCullFace(GL_FRONT);
    
    // Render bounding geometry
    _boundingBox.render();
    
    // Restore defaults
    glCullFace(GL_BACK);
}
    
void KameleonVolumeRaycaster::preRaycast(const RaycastData& data, ghoul::opengl::ProgramObject& program) {
    std::string stepSizeUniformName = "maxStepSize" + std::to_string(data.id);
    program.setUniform(stepSizeUniformName, _stepSize);

    std::string id = std::to_string(data.id);

    _tfUnit = std::make_unique<ghoul::opengl::TextureUnit>();
    _tfUnit->activate();
    _transferFunction->getTexture().bind();
    program.setUniform("transferFunction_" + id, _tfUnit->unitNumber());

    _textureUnit = std::make_unique<ghoul::opengl::TextureUnit>();
    _textureUnit->activate();
    _volumeTexture->bind();
    program.setUniform("volumeTexture_" + id, _textureUnit->unitNumber());

    program.setUniform("gridType_" + id, static_cast<int>(_gridType));
}
    
void KameleonVolumeRaycaster::postRaycast(const RaycastData& data, ghoul::opengl::ProgramObject& program) {
    // For example: release texture units
    _textureUnit = nullptr;
    _tfUnit = nullptr;
}
    
std::string KameleonVolumeRaycaster::getBoundsVsPath() const {
    return GlslBoundsVsPath;
}
    
std::string KameleonVolumeRaycaster::getBoundsFsPath() const {
    return GlslBoundsFsPath;
}

std::string KameleonVolumeRaycaster::getRaycastPath() const {
    return GlslRaycastPath;
}

std::string KameleonVolumeRaycaster::getHelperPath() const {
    return GlslHelperPath; // no helper file
}
    
void KameleonVolumeRaycaster::setStepSize(float stepSize) {
    _stepSize = stepSize;
}

void KameleonVolumeRaycaster::setGridType(VolumeGridType gridType)
{
    _gridType = gridType;
}
    
}