First, what do you need light for? Do you do paperwork? Is your desk in your window? You'll be getting afternoon sun. I'm recommending LED lighting to people, but Fred says it has a way to go in brightness and affordability. I recommend sky tubes to homeowners. I've had 2 in one of my houses.

Indeed an interesting thread an I must admit that I've been going cross-eyed extracting as much information from your two images as I can. A very challenging dilemma. I can't speak for the glazing. It's not my area of expertise. I'm inclined to agree with other comments in this thread re leaning towards internal window treatments. The long raking window at top presents special challenges and as Envirotecture has indicated it would meaning being open to the consideration of framing your view somewhat. Here are some ideas which might be worth considering. 1. A fixed curtain for the upper raking window. Given the room is very much about light, a sheer, though not providing the same insulating properties as curtains or heavier drapery, would nevertheless, provide some insulating benefit from the air-gapping effect. A fixed curtain (sheer or otherwise) is likely to be one of the cheaper components in the options I'm listing. 2. It's hard to tell from the images how much more the 'conventional' rectangular space beyond the couch extends. Assuming it does not extend the entire length of the side of the house you have a number of options available to you here. Options which could Include Soft Roman Blinds fronting on sunscreen roller blinds. Pelmets would provide substantive insulating benefits, but it is difficult to see from the image whether they would suit, and whether you would have sufficient height, or 'any height' above that window in which to mount them so as to minimise the loss of window view due to the stacking up of the Roman. The sunscreen rollers are less problematic in that regard and provide some insulation while still allowing light when the Romans are not lowered. If opting at any stage for Romans, ensure they are properly lined with pre-stiffened Roman Lining which provides better insulation, but almost more importantly, will not sag over time such is the case with many Romans that are lined with much cheaper curtain lining which is not pre-stiffened and does not afford the same degree of insulation. 3. Along the main alfresco expanse where the table is located, and under the previously proposed location of the fixed curtains along the raking window, a motorised or hand traversed S-Fold or Wave curtain fronting, yet again, more thermal sunscreen roller-blinds could present an attractive modern look in keeping with the modern style of the room and house. Of course, an issue is going to be stack-back when the curtains are open, however, the double layered protection of both a Wave or S-Fold curtain and Roller Blinds will provide superior insulating benefits to tinting throughout the year (not just summer) imho. 4. Other ideas include Plantation Shutters across the raking/eve window above. I doubt very much that plantation shutters would work along the lower 'framed' area as the stack-back effect if bi-fold, or loss of view if sliding, would be too much of a sacrifice, let alone the additional consideration of the cost of such treatment used so extensively. Although, the window treatments i have suggested for possible consideration do not necessarily offer optimum insulation (eg the exclusion of pelmets or use of heavy lined drapery), I believe that you there would be some offset in terms of a positive ROI over time due to the savings you will reap on your heating/cooling bills. I'm in Melbourne which is marginally warmer, and without adequate insulating window treatments, the heat loss through the glass is substantial and the heating/cooling bills frightening. 5. That's a hell of a lot of glass to treat whether you opt for a glazing solution which will provide primary benefit during the summer or conventional internal window treatments - whether drapery or blind. Either way the solution is likely to be costly. To keep the cost down you could always consider high quality Thermal Verticals which can come in a variety of slat sizes colours and textures and provide substantive savings over the Wave or S-fold solutions with less stack-back loss. Once again ensuring you purchase high quality verticals that will hold up to the Australian sun over the long haul is important. The cheaper stuff might look good but you'll be picking slats off the floor within 5 years if you are not careful. Here is an image from one of our own projects where high quality 'chain-less' verticals were used to cover large expanses of glass throughout the house in combination with thermal roller blinds. Of course, this treatment or the use of Wave/S-fold curtains would only provide part of the overall solution you require. 6. The only solution I didn't yet mention is the use of folding arm awnings. While they would provide benefits during the summer, they would be more than likely at the expense of your expansive view (or part thereof). Quality awnings whether manually operated or motorised are also costly. The only other comment I might make is that internal blind and curtain window treatments provide you with a high degree of flexibility. Romans, for example work well in combination with many other window treatments, either along side them, or in combination with each other in the context of the same window. The same can be said for the other treatments I have mentioned. The internal window treatments suggested can also facilitate the ability to support a style transition from one room or area to the next. - An important consideration if the house is of a uniform style throughout and you are wanting to 'mix it up a bit' or transition to styles that vary yet compliment the primary style or look you may have throughout the house. I'm sorry, it is difficult offering suggestions based on your two images, even though they are of good quality and detailed. I don't envy you with this 'design dilemma' ... though it certainly gets my vote as one of the more challenging ones I have seen in recent times, and in an area/topic where I felt I could contribute.

If the front of the house is west facing in Queensland and you have glass on that side of the house, in summer in the afternoon the sun beats down on this side for hours, heating up the whole house. There is some speculation on double glazing as some think that they do heat up, better than nothing. Once the sun hits the wall you are lost. These image are for north this is worst for west. A more passive means of cooling the house is to install tall enough thick leaves to the base trees on the western side so that they shade that elevation. Problem with that is that in winter, that sun would be nice. So you need trees that drop their leaves early winter and have them back on say September when the sun starts to heat up. Some trees hold onto their leaves till a few weeks before spring, so make sure you do your research and think root barrier up front to protect your footings. Photo below horizontal external shade screens, Another method is to shade the house with screens, i said house not windows. With western sun, it is low when it starts to clear the roof overhangs, so no amount of horizontal shade devices will make any real difference. The screens for western sun in Queensland must be of a vertical nature. So screens that hang OUTSIDE the house to around say 900 mm off the ground would be fantastic. Since the sun travels around the west from more south west in peak summer to west in winter, vertical blades tend to be ideal solution and should pivot, to deal with this moving sun. In the past, Queenslanders used to have these vertical screens on castors and they moved them around to suit the conditions, for some reason we did not learn from the past. This house the screens are not shading the walls at the bottom so they would still heat up. From the plans i see you are building in brick, so western sun and bricks in summer make an ideal oven. Takes bricks 12 hours to cool down depending on the colour. All material heats up in the sun, but bricks take longer to cool, light weight material which is properly insulated is a better choice and against popular opinion, glass is also a good choice, all better if vertically screened. Double brick tends to keep a house cooler and you might as well use the double brick for structure instead of the decorative nature of cavity brick house, but after a while that heats up and takes forever to cool. Studs hold up the roof, not the face bricks. Ever wonder why the house stands up during construction with stud wall and roof? Photo is vertical blades which pivot. A good landscape architect would be worth a look and they will know how to blend your style of house with the garden. North windows in Queensland even with no overhangs, (which is stupid in Queensland) do not get sun into the rooms, but in winter it might crawl in say 2 M which is nice. What are you doing with the roof and concrete tiles heat up nicely and the darker you make them the hotter they get, Colorbond is a good choice with all the hail we tend to get, or keep a stockpile of tiles for when they break. Colour also makes a difference to heat. Make sure you vent the roof space, whirly birds, and vented eaves or gable ends, make sure you fully insulate the roof and also ceiling, and choose a light colour. choose a style of external screens or trees to fit the house. See if that makes a difference to the report which is there to make your life better and we are talking the cost of air con for the life of the house, the reports are there to help save you money, maybe a bit more up front but worth it in the long running cost of a house. Ros

I agree that you need a blind like a roller or roman that goes up and out of kitty's way. Nobody has yet addressed your query about panel glides: Panel glides work best on large doors where there is room to stack the panels when opened. you will lose at least one third of your left glass door panel if you use panel glides and they also project into the room quite a bit.