FlowVis/LayerRenderable.cpp

#include "LayerRenderable.h"
#include <QGLWidget>

LayerRenderable::LayerRenderable(void)
{
        ltype = -1;     //nicht ausgewählt
        lchannel = -1; //nicht ausgewählt

        glGenTextures(1,&transferTexture);      //textur für transferfunktion
}

void LayerRenderable::setTransferFunction(const QImage& image)
{
        QImage transferImage = QGLWidget::convertToGLFormat(image);
        glBindTexture(GL_TEXTURE_1D,transferTexture);

        glTexParameteri(GL_TEXTURE_1D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
        glTexParameteri(GL_TEXTURE_1D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);

        glTexImage1D(GL_TEXTURE_1D,0,4,transferImage.width(),0,GL_RGBA, GL_UNSIGNED_BYTE,transferImage.bits());
}

void LayerRenderable::draw(GLuint* textures, QVector<Shader*> shaders, GLuint* dispLists, 
        float aspect, bool glyph, bool texture)
{
        if(ltype == -1 || lchannel == -1)
                return;

        float w = (aspect > 1.f) ? 1.f : aspect;
        float h = (aspect > 1.f) ? 1.f/aspect : 1.f;


        switch(ltype)
        {
        case TYPE_TEXTURE:              //Texture
                shaders[SHADER_TEXTURE]->bind();

                glActiveTexture(GL_TEXTURE0);
                glBindTexture(GL_TEXTURE_2D,textures[lchannel]);

                glActiveTexture(GL_TEXTURE3);
                glBindTexture(GL_TEXTURE_1D,transferTexture);

                glActiveTexture(GL_TEXTURE0);
                glColor4f(1.f,1.f,1.f,1.f);     
                glBegin(GL_QUADS);
                glTexCoord2f(0.0, 0.0f); glVertex2f(-w, -h);
                glTexCoord2f(1.0f, 0.0f); glVertex2f(w, -h);
                glTexCoord2f(1.0f, 1.0f); glVertex2f(w, h);
                glTexCoord2f(0.0f, 1.0f); glVertex2f(-w, h);
                glEnd();

                shaders[SHADER_TEXTURE]->unbind();
                break;

        case TYPE_ARROWS:               //Arrows

                shaders[SHADER_ARROWS]->bind();

                glActiveTexture(GL_TEXTURE0);
                glBindTexture(GL_TEXTURE_2D, textures[lchannel]);

                glActiveTexture(GL_TEXTURE1);
                glBindTexture(GL_TEXTURE_2D, textures[CHANNEL_X]);

                glActiveTexture(GL_TEXTURE2);
                glBindTexture(GL_TEXTURE_2D, textures[CHANNEL_Y]);

                glActiveTexture(GL_TEXTURE3);
                glBindTexture(GL_TEXTURE_1D, transferTexture);

                glCallList(dispLists[0]);

                glActiveTexture(GL_TEXTURE0);

                shaders[SHADER_ARROWS]->unbind();
                break;

        case TYPE_STREAMLINES:
                if (glyph) {
                        shaders[SHADER_ARROWS]->bind();

                        glActiveTexture(GL_TEXTURE0);
                        glBindTexture(GL_TEXTURE_2D, textures[lchannel]);

                        glActiveTexture(GL_TEXTURE1);
                        glBindTexture(GL_TEXTURE_2D, textures[CHANNEL_X]);

                        glActiveTexture(GL_TEXTURE2);
                        glBindTexture(GL_TEXTURE_2D, textures[CHANNEL_Y]);

                        glActiveTexture(GL_TEXTURE3);
                        glBindTexture(GL_TEXTURE_1D, transferTexture);

                        glCallList(dispLists[1]);

                        glActiveTexture(GL_TEXTURE0);

                        shaders[SHADER_ARROWS]->unbind();
                } else if (texture) {
                        shaders[SHADER_STREAMLINE_TEXTURE]->bind();

                        glActiveTexture(GL_TEXTURE3);
                        glBindTexture(GL_TEXTURE_1D, transferTexture);

                        glCallList(dispLists[1]);

                        glActiveTexture(GL_TEXTURE0);

                        shaders[SHADER_STREAMLINE_TEXTURE]->unbind();
                } else {
                        shaders[SHADER_STREAMLINES]->bind();

                        glActiveTexture(GL_TEXTURE0);
                        glBindTexture(GL_TEXTURE_2D, textures[lchannel]);

                        glActiveTexture(GL_TEXTURE3);
                        glBindTexture(GL_TEXTURE_1D, transferTexture);

                        glCallList(dispLists[1]);

                        glActiveTexture(GL_TEXTURE0);

                        shaders[SHADER_STREAMLINES]->unbind();
                }
                break;
        }
}
LayerRenderable::~LayerRenderable(void)
{
        glDeleteTextures(1,&transferTexture);   //Textur wieder löschen
}