Faux Marker Rendering

This tutorial outlines a quick method for creating faux-marker architectural renderings using SketchUp, Kerkythea (or another rendering program) and Photoshop. While I use a Kerkythea rendering as my base image in this tutorial, note that it is possible to work through this technique by replacing the rendering with a textured SketchUp export with shadows on. I use Kerkythea here because of its ability to more realistically render shade and shadows. Below is a view of the model and selected perspective directly in SketchUp. Because this technique requires a few image exports directly from SketchUp, I recommend creating a scene to make sure your view does not change.

Three layers are required for the final image. First change the view to Hidden Line, turn off profiles and export the view. The second image should be a looser, sketchier view. Here I chose to use the “sketchy classic” style, however others may better fit a different image. Third and finally is the colored rendering. I typically use Kerkythea as my program of choice for creating renders; however other programs would do just fine. Just remember to maintain the exact perspective and image size so that everything will line up later in Photoshop. As mentioned before this image could also be replaced by another SketchUp export containing colors, textures and shadows if you prefer. Below are my three images:

I’ll throw this in here although it is a completely optional step in the process. I sometimes like to use FotoSketcher to soften the rendering a little before bringing it into Photoshop. If you’re not familiar with the program it is freely available software that applies filters to images. Here I used the “Painting 3” drawing style to slightly blend like colors and blur the edges. The results are subtle but noticeable in the side-by-side comparison below. There are also several Photoshop filters that could be used to achieve a similar effect.

Now enter Photoshop and open the rendering first – this will serve as the base image. Next open the “hidden line” export. Desaturate the image and adjust the levels so that the image is black lines on a white background. Place the image on top of the rendering, set the layer mode to “multiply” and turn down the opacity to about 50%. Next open the “sketchy” image and place it on top. Again set the layer mode to multiply but keep the opacity a little higher at about 70%. All three images should line up perfectly so long as your view never changed.

Next comes the marker texture overlay. Create a new layer, set it to “multiply” turn down the opacity to about 30%. Select one of the “chalk” brushes and turn down the opacity to about 30%.

Select black or a dark gray from the color swatches and simply begin painting on the texture. Try to maintain a fairly consistent stroke direction and be as loose or careful as you wish when it comes to staying within the lines. The more you click and release the mouse, the more color variation and marker strokes will appear.

Below is a view after the texture has been applied to the entire image. By adjusting the opacity of the marker texture layer up and down you can make the effect more or less prominent. Adjusting the levels of the rendering layer will also lighten or darken the image.

Below is the final image with people and cars added into the scene to give it a little life. I also adjusted the perspective in Photoshop so that all of the vertical lines are parallel. I kept the marker texture layer dark to emphasize the effect but would generally lighten it up a bit. Total working time, including a fairly large Kerkythea rendering, was well under an hour.

Quick Illustrations

This is a breakdown of a quick illustration technique I have used to compose some smaller SketchUp models. The project shown is of a quick semester warm-up exercise from school where only visuals and no physical models were required. Since the project was quite small, I constructed the model atop what looks like a diorama base to give the building the look as if it is an actual model. Only three colors were applied to the entire model – orange for the shipping container, gray for the block and tan for everything else. In the end this became a technique I would use again to put together very quick faux basswood model visuals in a fraction of the time it would take to physically build one. While nothing can replace the ability to pick up, examine and critique a real world model, a collection of several perspectives of a project presented like this worked in a pinch.

The image below is a capture of the final SketchUp model. It’s a fairly simple construction, with the only real detail being the shipping container. Since the project was site-less, I situated the cabin on a square base to give the building an appearance of being an actual model. While this technique doesn’t always work with larger projects, I’ve found it quite useful with smaller buildings. I’ll note here that when using this technique I typically don’t include any glass or translucent materials. They can take away from the modeled look and also drastically increase renderings times.  As mentioned above only three colors were used, all applied in SketchUp. I’ve also locked in the view using the Scene tool since the final composition will consist of two images layered in Photoshop.

Once the view is locked I turned profiles ‘off’ under the Edge Style menu as shown above. Then I changed the Face Style to ‘monochrome’ and, making sure shadows are turned off, export the image as a jpeg under the File > Export menu. For my image I turned the sun back on and used Kerkythea to render the color and shadows; however you could directly export the view with all linework off and shadows on, as shown below. I prefer use a rendering engine such as Kerkythea because it tends to soften the image a bit and renders the shadows much more realistically. It also distances the image from the typical SketchUp look.

Once the two images are saved, it’s time to move to Photoshop. You should have two images similar to those shown below – one with colors and shadows and another with linework. Pull the linework on top of the rendering, set the layer to ‘overlay” and turn down the opacity. For this image the linework is at about 50% opacity.

I also added a few layers of grime on top of the composition to give the final image a little texture and color variation. Just perform an image search for ‘grime’ or ‘grunge’ and many images will pop up. These two layers were also set to ‘overlay’ and the opacity was turned down much lower – this time to only about 15%. The image above shows the second grime layer before the opacity was turned down.

Above is the final image. Besides the actual construction of the model in SketchUp, the image was composed in less than 10 minutes, including rendering the model in Kerkythea and playing around with layer opacities until I found a look that appealed to me. Below is the final poster for this cabin after a few images were compiled together with plans and text to give an outline of the entire project. The view broken down here can be seen faintly in the top left corner.

See the video breakdown of this illustration below:

A tutorial outlining a method to create quick architectural illustations using sketchup, the free kerkythea rendering engine and photoshop. The method is a means to produce quick stylized architectural images for presentation from any sketchup model with minimal post-processing and editing.

Sketchy Mid-Rise

The sketchy mid-rise illustration outlined here doesn’t distance itself too much from a direct SketchUp image export – instead it utilizes a few quick editing techniques to emphasize certain portions of the image while softening others that are not as crucial to the final composition. While certain SketchUp styles can be customized to give you an output similar to the final image shown here, I like to be able to independently adjust each image to get the final illustrative look I want. The final image as shown required the use of three programs for the main graphics– SketchUp, Kerkythea and FotoSketcher – all of which are completely free to download. Finally everything was brought into Photoshop for post processing. I should note that a very similar result can be achieved without the use of any rendering engine by instead substituting the Kerkythea rendering with an image exported directly from SketchUp with color and textures on and edges off. The reason I used Kerkythea here was to get the slight reflections on the glass faces and softer shadows.

Three main images were used as the base, pictured below. First is a SketchUp export using the “sketchy pen black” style while the second is a “hidden line” export. Third is a Kerkythea rendering for color, texture and shading. I’ll note here that the “hidden line” image should be desaturated and then level adjusted so that it is black and white.

Two of the images were then processed in FotoSketcher, both using the “painting5 (watercolor)” style. I chose to do this instead of using the watercolor filter in Photoshop because I feel that FotoSketcher both allows greater control over the filter settings and produces a better result. The Kerkythea rendering was processed first to lighten, texture and somewhat blur the image. The “sketchy pen black” SketchUp export was then processed using the same settings to give the linework a slightly more “painted” feel. The results appear below.

From there the two FotoSketcher images and the “hidden line” SketchUp export were brought into Photoshop. The Kerkythea rendering served as the base with the “hidden line” image in the middle and the “sketchy pen black” export on top. I set the layer mode of the sketchy image to “multiply” and turned down the opacity to 60%. From there I selected the middle “hidden line” layer, chose a soft brush with an opacity of about 20% and simply began erasing where I wanted color to show through. This step basically erases portions the “hidden line” image and reveals the rendering below.  As more passes are made with the eraser portions of the image will appear darker.

The picture below shows the image after several passes were made with the eraser and a sky was added. I also chose to lighten the linework at the edges of the image by using the eraser with lowered opacity on the top “sketchy” layer. Finally the vertical lines were made parallel by going to Edit > Transform > Perspective and dragging the top of the image while all three layers were selected.

I wanted to give the illustration a little additional hand drawn feel. Going back into SketchUp I created two new layers specifically for guidelines – one for the featured building in the center and another for the context buildings. I exported each separately, overlayed them in Photoshop, set the layer modes to multiply and erased the portions I did not want in the drawing with a soft brush. Finally the opacity of each layer was turned down so that the guides were visible yet subtle.

Finally, vehicles and figures needed to be placed in the image to add some life to the scene. Instead of manually placing cars into the image in Photoshop I created a new layer in the SketchUp model and placed them around the scene. In SketchUp I turned off all of the other layers and exported only the cars as seen below.

If possible I like to add vehicles this way because it maintains both the correct size and perspective of every car. Also, by keeping the vehicles on their own layer I was able to adjust the levels, colors and opacity so that everything blended together better. Lastly, figures were added manually (along with shadows) to complete the image.