painter_fixed.cpp Example File

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 #include "painter.h"
 #include "light.h"
 #include "lightmodel.h"
 #include "material.h"

 FixedFunctionPainter::FixedFunctionPainter()
 {
     glEnable(GL_LIGHTING);
     glEnable(GL_LIGHT0);
     glDisable(GL_CULL_FACE);
 }

 static void setMatrix(GLenum type, const QMatrix4x4 &matrix)
 {
     glMatrixMode(type);
     if (sizeof(qreal) == sizeof(GLfloat)) {
         glLoadMatrixf(reinterpret_cast<const GLfloat *>(matrix.constData()));
     } else {
         GLfloat mat[16];
         const qreal *m = matrix.constData();
         for (int index = 0; index < 16; ++index)
             mat[index] = m[index];
         glLoadMatrixf(mat);
     }
 }

 void FixedFunctionPainter::setMatrices
     (const QMatrix4x4 &mv, const QMatrix4x4 &proj)
 {
     setMatrix(GL_PROJECTION, proj);
     setMatrix(GL_MODELVIEW, mv);
 }

 static void setLight(int light, const Light *parameters,
                      const QMatrix4x4& transform = QMatrix4x4())
 {
     GLfloat params[4];

     glMatrixMode(GL_MODELVIEW);
     glPushMatrix();
     glLoadIdentity();

     QColor color = parameters->ambientColor();
     params[0] = color.redF();
     params[1] = color.greenF();
     params[2] = color.blueF();
     params[3] = color.alphaF();
     glLightfv(light, GL_AMBIENT, params);

     color = parameters->diffuseColor();
     params[0] = color.redF();
     params[1] = color.greenF();
     params[2] = color.blueF();
     params[3] = color.alphaF();
     glLightfv(light, GL_DIFFUSE, params);

     color = parameters->specularColor();
     params[0] = color.redF();
     params[1] = color.greenF();
     params[2] = color.blueF();
     params[3] = color.alphaF();
     glLightfv(light, GL_SPECULAR, params);

     QVector4D vector = parameters->eyePosition(transform);
     params[0] = vector.x();
     params[1] = vector.y();
     params[2] = vector.z();
     params[3] = vector.w();
     glLightfv(light, GL_POSITION, params);

     QVector3D spotDirection = parameters->eyeSpotDirection(transform);
     params[0] = spotDirection.x();
     params[1] = spotDirection.y();
     params[2] = spotDirection.z();
     glLightfv(light, GL_SPOT_DIRECTION, params);

     params[0] = parameters->spotExponent();
     glLightfv(light, GL_SPOT_EXPONENT, params);

     params[0] = parameters->spotAngle();
     glLightfv(light, GL_SPOT_CUTOFF, params);

     params[0] = parameters->constantAttenuation();
     glLightfv(light, GL_CONSTANT_ATTENUATION, params);

     params[0] = parameters->linearAttenuation();
     glLightfv(light, GL_LINEAR_ATTENUATION, params);

     params[0] = parameters->quadraticAttenuation();
     glLightfv(light, GL_QUADRATIC_ATTENUATION, params);

     glPopMatrix();
 }

 static void setLightModel(const LightModel *lightModel)
 {
     GLfloat values[4];
 #ifdef GL_LIGHT_MODEL_TWO_SIDE
     if (lightModel->model() == LightModel::TwoSided)
         values[0] = 1.0f;
     else
         values[0] = 0.0f;
     glLightModelfv(GL_LIGHT_MODEL_TWO_SIDE, values);
 #endif
 #ifdef GL_LIGHT_MODEL_COLOR_CONTROL
     if (lightModel->colorControl() == LightModel::SeparateSpecularColor)
         values[0] = GL_SEPARATE_SPECULAR_COLOR;
     else
         values[0] = GL_SINGLE_COLOR;
     glLightModelfv(GL_LIGHT_MODEL_COLOR_CONTROL, values);
 #endif
 #ifdef GL_LIGHT_MODEL_LOCAL_VIEWER
     if (lightModel->viewerPosition() == LightModel::LocalViewer)
         values[0] = 1.0f;
     else
         values[0] = 0.0f;
     glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER, values);
 #endif
 #ifdef GL_LIGHT_MODEL_AMBIENT
     QColor color = lightModel->ambientSceneColor();
     values[0] = color.redF();
     values[1] = color.blueF();
     values[2] = color.greenF();
     values[3] = color.alphaF();
     glLightModelfv(GL_LIGHT_MODEL_AMBIENT, values);
 #endif
 }

 static void setMaterial(int face, const Material *parameters)
 {
     GLfloat params[17];

     QColor mcolor = parameters->ambientColor();
     params[0] = mcolor.redF();
     params[1] = mcolor.greenF();
     params[2] = mcolor.blueF();
     params[3] = mcolor.alphaF();

     mcolor = parameters->diffuseColor();
     params[4] = mcolor.redF();
     params[5] = mcolor.greenF();
     params[6] = mcolor.blueF();
     params[7] = mcolor.alphaF();

     mcolor = parameters->specularColor();
     params[8] = mcolor.redF();
     params[9] = mcolor.greenF();
     params[10] = mcolor.blueF();
     params[11] = mcolor.alphaF();

     mcolor = parameters->emittedLight();
     params[12] = mcolor.redF();
     params[13] = mcolor.greenF();
     params[14] = mcolor.blueF();
     params[15] = mcolor.alphaF();

     params[16] = parameters->shininess();

     glMaterialfv(face, GL_AMBIENT, params);
     glMaterialfv(face, GL_DIFFUSE, params + 4);
     glMaterialfv(face, GL_SPECULAR, params + 8);
     glMaterialfv(face, GL_EMISSION, params + 12);
     glMaterialfv(face, GL_SHININESS, params + 16);
 }

 void FixedFunctionPainter::selectMaterial(Material *material)
 {
     ::setLight(GL_LIGHT0, light);
     ::setLightModel(lightModel);
     ::setMaterial(GL_FRONT_AND_BACK, material);
     glDisable(GL_TEXTURE_2D);
     glEnableClientState(GL_VERTEX_ARRAY);
     glEnableClientState(GL_NORMAL_ARRAY);
     glDisableClientState(GL_TEXTURE_COORD_ARRAY);
 }

 void FixedFunctionPainter::selectTexturedMaterial(Material *material)
 {
     ::setLight(GL_LIGHT0, light);
     ::setLightModel(lightModel);
     ::setMaterial(GL_FRONT_AND_BACK, material);
     glEnable(GL_TEXTURE_2D);
     glEnableClientState(GL_VERTEX_ARRAY);
     glEnableClientState(GL_NORMAL_ARRAY);
     glEnableClientState(GL_TEXTURE_COORD_ARRAY);
     glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
 }

 void FixedFunctionPainter::setVertices(const float *array, int stride)
 {
     glVertexPointer(3, GL_FLOAT, stride * sizeof(float), array);
 }

 void FixedFunctionPainter::setTexCoords(const float *array, int stride)
 {
     glTexCoordPointer(2, GL_FLOAT, stride * sizeof(float), array);
 }

 void FixedFunctionPainter::setNormals(const float *array, int stride)
 {
     glNormalPointer(GL_FLOAT, stride * sizeof(float), array);
 }