MATLAB: Bizare problem with FaceAlpha and rendering

facealphapatchredererrenderer;patch;facealpha

Hi,
I have a very strange problem so i want to create a series of patch objects and plot them together (for simplicity in this example there is only one object):
X =900000;
Y =115;
Z =100;
origin = [100000,5,100];
MINX = 0.1;
MAXX = 1000000;
MINY = 0.000001;
MAXY = 120;
MINZ = 0.01;
MAXZ = 1000;
clf
h(1) = axes('Position',[0.2 0.2 0.6 0.6]);
vert = [origin(1) origin(2) origin(3); ...
  origin(1) origin(2)+Y origin(3); ...
  origin(1)+X origin(2)+Y origin(3); ...
  origin(1)+X origin(2) origin(3); ...
  origin(1) origin(2) origin(3)+Z; ...
  origin(1) origin(2)+Y origin(3)+Z; ...
  origin(1)+X origin(2)+Y origin(3)+Z; ...
  origin(1)+X origin(2) origin(3)+Z]; 
fac = [1 2 3 4; ...
  2 6 7 3; ...
  4 3 7 8; ...
  1 5 8 4; ...
  1 2 6 5; ...
  5 6 7 8];
hold on;
bob = patch('Faces',fac,'Vertices',vert,'FaceColor','b','FaceAlpha',0.5);
light('Position',[1 3 2]);
light('Position',[-3 -1 3]);
material shiny;
alpha('color');
alphamap('rampdown');
camlight(45,45);
lighting phong;
view(30,30);
set(gca,'XLim',[MINX MAXX],'YLim',[MINY MAXY],'ZLim',[MINZ MAXZ]);
set(gca,'XScale','log','YScale','log','ZScale','log');
%set(gcf, 'Renderer', 'OpenGL');
Ok so the issue is that up until the point where i set the scales to log the objects are semi transparent (FaceAlpha 0.5), however when set they then become solid again and no matter what value of FaceAlpha they remain this way.
I looked around and found a suggestion to set the rendering to open glide (last line of code which is commented) but this is when it becomes even more strange. If you run the code with the last line above you do get transparent objects but the log scales change completely and appear to be normal scales again despite being set to log values!
Can anyone help me with this? I need to get transparent objects with the log scales obtained with the code above (minus the openGl render code which changes the log scale)
Also has anyone encountered this problem before? Why on earth would changing the renderer change the log scale of the plot???
Thanks
Matt
EDIT: BTW im using r2008b EDIT: OK so i just found that openGl doesnt support log scales so thats one problem sorted but how then can i get transparent objects with log scales in matlab??

Best Answer

Unfortunately you won't be able to create a plot with log scales and transparent objects.
OpenGL is the only renderer that supports transparency, but it does not support log scales. The other renderers (ZBuffer, Painters) do support log scales, but no transparency. You can find more information on renderers here:
http://www.mathworks.com/support/tech-notes/1200/1201.html
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