Friday, May 28, 2010

GIMP Tutorial: Quick Retro Dots & Making A Permanent Brush *Beginners*

Retro Dots

I found two tutorials on making retro dots. So either, 1) they're not all that popular, or 2) people are just using the circle selection or brushes to create them. Whichever the case, even if its all of the above or something else, the two tutorials I read on making them were just too complicated to follow and use (and done for Photoshop). A RetroDots plug-in found at Philipp's website is geared for Photoshop, requires PSPI to run in GIMP, and at least for me, is not the whole effect I was seeking.

The example found at this Photoshop tutorial is close to what I want to achieve, but alas, jumping through all these render cloud hoops is just not my thing. Instead, I'll simplify it to suit my use and share that here.

Tutorial YouTube video of the following steps can be found here.

Step 1:

Create your own sized drawing with a white background, then add a transparent layer, name it dot1.

On the transparent "dot1" layer, draw out some rectangle selections of various thicknesses, like shown: (TIP: After making the first selection, hold down the Shift key while creating the subsequent bands)

Using the Paintbucket tool, fill with whatever foreground color of your choice. I chose black because I want to convert my dot into a brush.

Step 2:

Select - None

Go to Filters - Distort - Polar Coordinates. Use the following settings and select "OK":

That's the first dot. If you want dots of differing thicknesses, repeat these steps, just draw out your bands thicker or thinner. If the first dot is suitable and you wish to replicate it, no problem.

I believe the brush image size limit in GIMP is 520 x 520 pixels, someone correct me if I am wrong. So if your image drawing size is well over 520 pixels in any direction, we will need to resize the dot layer to fall under 520 in order for it to display correctly

Right click the dot1 layer in the Layers dialog, select Scale Layer. Rescale the image to fall within the 520 x 520 limit. Make sure your pixel ratio chain is linked on the Scale Layer options menu.

Edit - Copy the dot1 layer, if you just want to use this dot for this drawing session only - OR - to make the dot brush permanent, perform the following steps:

Step 3: (permanent brush only - skip this step and go to Step 4 if you just want to make quick, temporary dots)

Right click the dot1 layer and Merge down onto the white background.

Go to Image - Autocrop Image (you should now have an image just the size of the dot):

Go to Image - Mode - Greyscale.

Then on the Layers dialog, right click the layer and select Flatten Image.

File - Save As - (name your file retrodot1.gbr or a name of your choice, just use the .gbr extension).

Make sure to browse to save the brush to your Users .gimp-2.6/brushes folder. You can accept the default spacing of 10, but on the description, in order to get it to show up toward the top of your brushes, add a . (period) before the name in the description (like .dots1)

Refresh your brushes.

Performing these steps allow us to use any foreground color we wish when using the dots brush.

Step 4:

Create a new transparent layer, name it dots2.

If you now look under your brushes menu, you should see the dot1 as the very first image at the top.

The trick for changing colors for the dots is to use "Use color from gradient" and make both the foreground and background colors the same, while using the Pencil tool, Paintbrush tool, or Airbrush tool. Brush away!

Resize the brush scale and change the colors to suit. You can even create multiple layers of dots and change the layer modes or add patterns or adjust opacity levels to get some really sweet effects.

The following is an example of several layers set at different modes (multiply, screen, difference, and overlay). I strongly encourage you to create various layers of different colored dots and set each mode differently just to see the effects it gives.

I thought of making my dots with grunge backgrounds and dot patterns:

Nothing really special here, just 4 layers with a bottom-most layer with grunge pattern background, and 3 multiply mode layers of  dots of different sizes. The trick is to use the Color Select tool for each dot layer (selecting the dot), and fill with the Bucket Fill tool, using grunge patterns instead of color.

I hope this helps. Thank you for stopping by.

Saturday, May 22, 2010

GIMP Tutorial: Working With The Shapes Paths Script

Shape Paths is one of the very first scripts I loaded into GIMP. My goal at the time was to try and make GIMP as comfortable to use as Paint Shop Pro's "shapes" gallery. There is a significant difference between both applications, since GIMP doesn't have its own internal "shapes" library and you are required to save your shapes into a .xcf file in order to retain them.
When I started using paths in GIMP, I was originally thinking along the lines of creating "vectors". Unfortunately, GIMP is a raster based program. So, if vectors are what you're wanting, it's best to build them directly into whichever vector application you decide to use. Inkscape is a free vector program that uses the svg format.
If you have never downloaded scripts or plug-ins into GIMP, read my tutorial on that, here.
Shape-path-0.91.scm is the most current version. Don't make the same mistake I did and attempt to install both the .7 and 0.91 versions. Just stick with 0.91. Once you have it installed and the scripts refreshed, you should find the script under the Script-Fu/Shape Paths menu at the top of your drawing window.
There are 14 path options, a few of which are self-explanatory, but if you feel intimidated by the menu prompts for any of these options, you aren't alone. I'll do my best to break down the menus with screenshots so that they make sense for you to use them.
Advanced Rounded Rectangle:
The menu prompt

If that doesn't intimidate you, that's good, but it's easy to see how it could.
Let's break this menu down further to make it easier to comprehend:

You might be asking yourself, "Is there an easier way to achieve this?" The answer is yes, although you might lose node accuracy. Simply use the Rectangle selection tool, set to rounded at 25 degrees, and save the resulting selection to a path (Select – To Path). However, check the node points (Path dialog – tick the Eye icon) between the two path variations, you'll notice a difference in the number of nodes. If accuracy is important to you, stick with the shape path option (fewer nodes).
Circle and Ellipse
Both are pretty self-explanatory. Select your x and y positions, and input your radius (how wide and tall you want the ellipse to be).
Flowers and Spikes
This totally baffled me when I first used it. After a little tinkering with the inputs it soon became somewhat easier to use. The menu defaults:

Locating center on the drawing (x and y) not a problem. Radius, think in terms of dimensions – or – (radius x 2 = diameter) so a 100 px radius will give you a diameter of 200 px.
Now, I'm not going to even pretend I know what I am talking about in regards to the Factors A and B, and their angular displacements. But what I will tell you is that if you experiment in small increments, and keep the angular displacements symmetrical (90 degrees for both) you'll get more pointed flower petal shapes, depending on how many sides you choose to implement and how high you make the factors of those displacements. Here is an example of a 7 petal flower I made using the following settings on a 640 x 640 px drawing:

If I had kept both factors A and B positive, the curve points would have pushed both sides of the petal/spike in the same direction, much like a tri-fold paper being folded flat. I truly tried to find more information on the mathematics of this path function and came up short (when comparing it to the code within the script). It would be really cool if Jon Stipe or Pucelo (the authors of the script) chimed in and explained this process more definitively and thoroughly.
Easier way to perform this function? Not really, especially if you're wanting symmetry. You could always throw out some path points and work out the bezier curve points on your own (you'll need a grid and guidelines), but if the mere changing of a few numbers on this menu is all that's needed, why bother? I've made some really cool designs using this script. Experimentation is strongly encouraged, but keep in mind, make small changes, gradually. A combination of paths make some pretty interesting designs.
Also, if anyone viewing this post knows what the factors and angular displacements are all about, please chime in via comments, and I'll add it to this post.

Pretty straight forward to use. The difference between the Outer and Inner radius determines how short or long your gear teeth will be. The greater the number between them, the longer your gear teeth will be. Although there is no actual way to manipulate the nodes using the script's menu options, you can physically edit the path points and make some really interesting designs. Gears, like Flowers and Spikes need a tutorial all their own.
One thing I want to point out: it's not an oval if all 4 radius sides are the same. To elongate to oval shapes, make L and R sides larger or smaller than the Top and Bottom.
One important note for miters, when using Polygon: (360/(numbers of sides x 2) gives you miter degrees. How is this important? Well, say you want to make an 8 sided stop sign, but you're not sure what rotation to use to flatten the top and bottom sides. To get the octagon to lay on its side (flat) rather than its point, you add the miter degree to your rotation. You can also get some really cool designs overlapping and merging rotated polygons. Note the example below:
Rectangle and Rounded Rectangle
Straightforward to use.
Sine Wave
Amplitude is actually half the distance from peak to valley, so if you selected amplitude to be 75 px, the sine wave from peak to valley will equal 150 px (75 pixels times 2). 
Wavelength is the distance between the cycles, so if you had 3 cycles and wavelengths were set to 70 px, your sine wave would be 210 px in length. This is good to know if you're using sine wave decoratively.
One other important note: even if you pick the exact center of your image, the wave does not center itself on those x and y points, it starts the wave from center in L to R orientation.
Square Wave
Each setting was done individually, not all at the same time.
Just like Sine Wave, positioning at exact x and y center does not center the wave, it starts from that point in L to R orientation.
Straightforward to use.
Identical to Gears in every way except each star segment comes to a point, not a flat top. I will be using this function for my next tutorial on making raster clip art.
Triangle Wave
Somewhat like Square Wave, minus the convergence and displacement. Instead it has rounding and shearing. Note the image below:
I hope this brief description gives you a better idea of how these shapes can be used via menu options. Should I get more information on Flowers and Spikes, I'll repost it here. Be looking forward to my next tutorial on creating raster clip art using the "Star" shape path script.
Thank you for stopping by! 

GIMP Tutorial: Making Sun Clip Art Using Paths *BEGINNERS*

My last post was a sort of introduction to the usefulness of the shape path script. If you haven't read that or downloaded the script, you can check that here.

The use of paths really speeds up and enhances your images. Let's get started with the sun clip art:

Step 1:

Open a new drawing 640 x 640 px, with a white background, add a new transparent layer and name it "rays".

Center two guidelines (vertically and horizontally) on your image at 320 px.

Go to Script-Fu/Shapes Path/Star and enter the following settings:

Activate the path selection for the star path by clicking the "Path to selection" icon  in the Paths dialog.

Select the Ellipse Select tool and enter the following settings:

Draw out a circle from center (320, 320) like shown:

Save the new selection to a path (Select - To Path).

Step 2:

Next set up your Blend (Gradient) colors of foreground (ffe400) and background (ffa800).

Your Blend tool settings should be like shown:

Drag out the Blend tool from center of the drawing, like shown below:

In the Paths dialog, apply the background yellow/orange to the current path as a 2 px stroke (right click path and select stroke path):

Step 3:

Add a new transparent layer and name it "sun".

Use the Ellipse Select tool, with the same settings as before (except change the mode from Subtract to Replace), and create a center circle inside the rays (save the circle as a path).

Using the Blend tool, draw out your gradient (same settings used with the rays above, only swap the foreground and background colors):

The result after adding a 2 px yellow/orange stroke to the circle:

Step 4:

Add a new transparent layer and name it "face".

Use the Ellipse select tool, to create one eye, fill the selection with a dark brown color. Duplicate the layer, and flip it horizontally:

Use the Path tool to create the mouth and cheeks, using a 4px  dark brown stroke:

Step 5:

Add a new transparent layer and name it "Glow".

Using the Ellipse Select tool, create an area over the top section of the sun, like shown:

Set your foreground color to white, and using the Blend tool, with your Gradient set at FG to Transparent, fill the ellipse selection with the white gradient:

With the Blend:

Now we need to add a new transparent layer and name it "sheen".

We're going to add a brassy like sheen to the lower portion of the sun. You want the brass color (d57709) to be slightly darker than the yellow/orange color currently being used in the sun.

Using the Ellipse Select tool, create a larger ellipse selection like shown:

Remove the selection (Select - None).

Add a Gaussian blur of 10 px.

Move the Sheen layer below the face layer.

Lower the opacity of the Sheen layer to 50.

Step 6:

Finally, add a new transparent layer and name it "cheeks". This layer should be top-most.

Set the Airbrush tool brush to Round Middle Soft 40, scale at 90, and foreground color to (ff7e00).

Using the default Airbrush settings, apply the Airbrush to the cheeks, like shown:

That's it, you're done!

Wednesday, May 5, 2010

GIMP Tutorial: How To Make Your Own Bumblebee *BEGINNERS*

Step 1:

Open a new drawing with a white background, add a new transparent layer, name it "wings". Follow similar steps found in my  Dragonfly tutorial shown in Step 1. The shape of the wings will be somewhat different, but the concept of how they are made remains the same. Draw out one set of wings using the Path tool:

In the Path dialog, duplicate the path and then using the Flip tool, (make sure to set it to Path) flip it horizontally.

You might have to use the Move tool and Rotate tool to get your flipped wing to line up like you see in the image above. Just remember to select the Path option on both tools.

Follow Steps 2, 3, and 4 in the dragonfly tutorial to complete the wings.

Your result should be similar to the following:

Step 2:

Add a new transparent layer and name it "body". Using the Path tool, click out a path like the following, then round out your nodes to resemble a pear shape with a little stinger at the bottom:

Select Path to Selection and fill it with either yellow or black (your preference). Keep the body selection active throughout the next series of the following steps:

Select the Ellipse tool and set the mode to (Subtract from the current selection). Starting at the top, create an ellipse to subtract a portion of the body, like shown:

Fill the selection with the opposite color (yellow or black). Keep the selection active, create another ellipse, like shown, and repeat this process to the bottom of the body, keeping the stinger black.

In the Path dialog, stroke the body path with yellow at 2 px.

Step 3:

Create a new transparent layer, name it "reflection".

Using the Airbrush tool with color set to white, paint a path on the body, like shown:

Go to Filters - Blur - Gaussian Blur set to 25 px

Step 4:

Create a new layer and name it "head".

Using the Path tool, lay out a path that resembles a heart shape with 3 mounds, instead of 2. Round out your points (nodes) like shown:

Convert the Path to a selection, and using the colors (ffc000) and (bf9000), use the Blend tool to create a radial gradient, from the lowest middle point of the head, like shown:

Create a new transparent layer and name it "eyes".

Using the Path tool, lay out a path that resembles an "alien" eye, like shown:

In the Path dialog, duplicate the eye path. Then with the Flip tool set on "affect" - Path, flip it horizontally:

As you can see the right side needs to be moved over a little more, no problem. With the Path tool and right eye path selected, hold down the ALT key and drag the right eye and even it out.

Use the Blend tool, with radial gradient colors set to black and medium gray, and convert each eye path to selection and fill. Stroke each eye path with yellow at 2px:

Now that we can see the eye placement on the head, we can highlight it to improve the look.

Create a new transparent layer and name it "highlights".

Using the Airbrush tool with foreground color set to white, brush on narrow white lines, as shown:

Filters - Blur - Gaussian Blur at 15 px.

Step 5:

For the antennae and legs, revert back to my Dragonfly tutorial for the specifics in (Step 10) or (Step 7) in the Ladybug tutorial on using the Stroke Tapered Path effect.

The leg paths do not need to be duplicated and flipped since your leg paths require being both in front of the body layer and behind the body layer, which means you need to create two layers, place one layer directly below the body layer, and the other directly above the body layer. You could duplicate and flip the paths if you wanted to, but since its not that complicated, I preferred to just create 4 individual paths. The layers are set up like shown:

For the legs, I used the following settings on the Stroke Tapered Path menu:

Here is how I set the legs up on the image:

Two in front of the body, and two behind the body, plus I set up two additional transparent layers for both sets of legs and used a 1 px white stroke on each leg path for highlighting with a 2 px Gaussian blur (much like we did for the head and the body highlighting):

Finally, the antennae. Create a new transparent layer below the "head" layer and name it "antennae". Create two paths like shown below. Use the same Stroke Tapered path settings from the legs, with the exception of the START taper width (change it to 4, leave the rest the same):

Before the tapered paths.

Now add the little balls at the end. (Just use Airbrush tool, foreground set to black. Add a smaller white highlight afterwards (use the fuzzy circle brush for highlighting).

That completes the steps needed for this tutorial. You can go beyond these steps and add textures and color enhancements to improve the overall appearance.

The final product:

Thank you for stopping by.