/**
* <code>set</code> sets the OpenGL fog values if the state is enabled.
*
* @see com.jme.scene.state.RenderState#apply()
*/
public void apply() {
final GL gl = GLU.getCurrentGL();
// ask for the current state record
RenderContext<?> context = DisplaySystem.getDisplaySystem().getCurrentContext();
FogStateRecord record = (FogStateRecord) context.getStateRecord(RS_FOG);
context.currentStates[RS_FOG] = this;
if (isEnabled()) {
enableFog(true, record);
if (record.isValid()) {
if (record.fogStart != start) {
gl.glFogf(GL.GL_FOG_START, start);
record.fogStart = start;
}
if (record.fogEnd != end) {
gl.glFogf(GL.GL_FOG_END, end);
record.fogEnd = end;
}
if (record.density != density) {
gl.glFogf(GL.GL_FOG_DENSITY, density);
record.density = density;
}
} else {
gl.glFogf(GL.GL_FOG_START, start);
record.fogStart = start;
gl.glFogf(GL.GL_FOG_END, end);
record.fogEnd = end;
gl.glFogf(GL.GL_FOG_DENSITY, density);
record.density = density;
}
applyFogColor(getColor(), record);
applyFogMode(densityFunction, record);
applyFogHint(quality, record);
applyFogSource(source, record);
} else {
enableFog(false, record);
}
if (!record.isValid()) record.validate();
}
private void applyFogSource(CoordinateSource source, FogStateRecord record) {
final GL gl = GLU.getCurrentGL();
if (supportsFogCoords) {
if (!record.isValid() || !source.equals(record.source)) {
if (source == CoordinateSource.Depth) {
gl.glFogi(GL.GL_FOG_COORDINATE_SOURCE_EXT, GL.GL_FRAGMENT_DEPTH_EXT);
} else {
gl.glFogi(GL.GL_FOG_COORDINATE_SOURCE_EXT, GL.GL_FOG_COORDINATE_EXT);
}
}
}
}
private void applyFogColor(ColorRGBA color, FogStateRecord record) {
final GL gl = GLU.getCurrentGL();
if (!record.isValid() || !color.equals(record.fogColor)) {
record.fogColor.set(color);
record.colorBuff.clear();
record
.colorBuff
.put(record.fogColor.r)
.put(record.fogColor.g)
.put(record.fogColor.b)
.put(record.fogColor.a);
record.colorBuff.flip();
gl.glFogfv(GL.GL_FOG_COLOR, record.colorBuff); // TODO Check for float
}
}
private void applyFogHint(Quality quality, FogStateRecord record) {
final GL gl = GLU.getCurrentGL();
int glHint = 0;
switch (quality) {
case PerVertex:
glHint = GL.GL_FASTEST;
break;
case PerPixel:
glHint = GL.GL_NICEST;
break;
}
if (!record.isValid() || record.fogHint != glHint) {
gl.glHint(GL.GL_FOG_HINT, glHint);
record.fogHint = glHint;
}
}
private void enableFog(boolean enable, FogStateRecord record) {
final GL gl = GLU.getCurrentGL();
if (record.isValid()) {
if (enable && !record.enabled) {
gl.glEnable(GL.GL_FOG);
record.enabled = true;
} else if (!enable && record.enabled) {
gl.glDisable(GL.GL_FOG);
record.enabled = false;
}
} else {
if (enable) {
gl.glEnable(GL.GL_FOG);
} else {
gl.glDisable(GL.GL_FOG);
}
record.enabled = enable;
}
}
private void applyFogMode(DensityFunction densityFunction, FogStateRecord record) {
final GL gl = GLU.getCurrentGL();
int glMode = 0;
switch (densityFunction) {
case Exponential:
glMode = GL.GL_EXP;
break;
case Linear:
glMode = GL.GL_LINEAR;
break;
case ExponentialSquared:
glMode = GL.GL_EXP2;
break;
}
if (!record.isValid() || record.fogMode != glMode) {
gl.glFogi(GL.GL_FOG_MODE, glMode);
record.fogMode = glMode;
}
}