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How to Create a Pirate Treasure Chest in Paint Tool SAI

Final product image
What You'll Be Creating

Who doesn't like to play games? In this tutorial we will draw a game object that can also be used as a game icon. The main theme is a pirate or underwater icon, and our object is a treasure chest. We will work in Paint Tool SAI, using all its useful tools and techniques, such as filters for color adjustment, simple tricks for faster work, and other neat stuff.

1. Create a Sketch of the Treasure Chest

Step 1

We'll begin with a New Canvas, about 3200 px width and 2400 px height. The basic shape of the treasure chest is a cube, so let's start to build the perspective of this shape, which has all sides parallel to each other. However, in this case, we can make the edges of the cube not exactly equal, because our chest isn't a correct cube.

Take either a Marker tool with 100% density and 20 px size, or any other tool that is most comfortable to work with. I use the Marker because for now we don't need many details and can concentrate only on very basic forms, and the Marker tool allows us to do just that.

Create perspective for a chest

Step 2

After creating the basic shape of the perspective, we can continue with developing an object. Make a New Layer on top of the base layer and, using the shape of the perspective as a guide, begin to add more form to the treasure chest.

You can find some inspirational images here:

Initial shape of the chest

Also, add decorative pieces, such as patterns and tapping. You can do it either by creating a New Layer on top of others and painting on top of the base sketch, or with the help of the Eraser tool.

Developing shape of the chest

Step 3

Experiment with the shape of the object, and when you feel satisfied with it, add more details, such as gold, pearls, diamonds, and anything you think can be found in the treasure chest.

I've also added a few starfishes here and there, to imply that this chest has spent some time underwater and perhaps was owned by pirates.

Further detailing of the sketch

2. Create Line Art Based on the Sketch

Step 1

Now we can start drawing line art based on the finished sketch. First, Merge down all the sketch layers into one and turn down the opacity of this layer to about 15-20%. This way you can more clearly see the parts that you're working on and won't mess up with the new lines.

Second, take the Crayon tool, or, if you don't have it in your version of Paint Tool SAI, use the Pen tool instead. Check the settings on the image, and make sure you're using quite a small brush with a soft angle.

Beginning work on line art

Step 2

Usually I work on big parts at the beginning, with each step adding more details. Try to make lines in one go. If needed, practice on another canvas until you feel confident in your lines.

If you make a mistake, don't panic. Just use the Eraser tool or undo your moves (Command-Z).

Delopment of the line art

Step 3

Gradually work on the detailing, and when everything is ready, hide the sketch layer. You may find some dirty parts on your line art, and if so, use the Eraser tool to clean them up.

It's time to make the treasure chest more lively by adding colors.

Finished clean line art

3. Create Layers With Base Colors

Step 1

Make a New Layer beneath the layer with the line art and fill it in with a dark color using the Bucket tool. This is done so all the object's colors will be more visible, which will help you stay within the borders.

Adding background beneath the line art

Also, you should choose some basic colors for a palette. When selecting, make sure that the colors are rather contrasting to each other. If you have some hesitation about this task, the Color Wheel can help you. Simply select colors that are opposite each other on the wheel.

Palette for the chest

Step 2

You should use separate layers for every color, so when you want to change one color to another, it will be very easy. Create a New Layer for each of the colors, and place them on top of each other.

To fill in areas with color faster, you can use one simple technique. At first, using the Air Brush or the Pen tool, create an outline of the big color area, making sure that every part of the area is checked. Then take the Bucket tool and fill in the entire area with just one click of the mouse. 

Flat base colors

Step 3

Make sure there are no empty spots in your object, and if you noticed some, paint them over with the Air Brush.

As we previously made separate layers for every color, now we can easily play with them. Try to change the color of the starfishes, a lock, or any other thing, to see what works best for the particular object. You can do that by filling in the layer using the Bucket tool.

Two background color variations

Also try different versions of the background. I liked the light background more and decided to stick with it.

4. Adding Shadows, Lights, and Reflections

Step 1

At first, let's make some basic shadows. Take the Air Brush with a soft, cold color. You can select this pale violet, or whichever you prefer. 

Make a New Layer beneath the layer with the line art, and set its Mode to Multiply with about 60% opacity. Choose the place where your light source will come from, for example from the top left corner of the canvas. And keeping that in mind, apply shadows to the chest and background.

Adding layer with shadows

Step 2

This time we will add lights. Once again, make a New Layer and place it beneath the layer with the line art, but on top of the layer with the shadows. Set its Mode to Overlay with 70% opacity.

Remember about the light source you chose before, and begin to add lights using the Air Brush. You can experiment with colors like soft violet, orange, and beige.

Adding layer with lights

Step 3

With our basic shadows and lights in their places, we can work on reflections now. This is a pretty simple thing to do—just mix neighbouring colors with each other. But don't overdo it, because we need only very slight reflections.

Working on reflects

When you've finished with the reflections, notice that the image is much softer now. Exactly what we wanted. And now, with all the preparations done, we can go to the next big step.

Finished initial reflects

5. Detailing the Treasure Chest

Step 1

We'll start from the top and gradually move throughout the drawing. This step is about making more details and adding textures, so let's do that.

I suggest we add some cracks on the chest and paint over the outline. Use the Air Brush with a soft angle for this kind of work.

Render of the top

The close-up shows that I've hidden the line art, added more reflections and cracks, and cleaned up the lines.

Close-up of the side

Step 2

You go from very basic shadows and lights to the detailed piece. When painting starfishes, blend them into the drawing, adding more reflections if needed. I've made those starfishes blue, but you can make them coral, yellow, violet, or anything. Try out different colors; they might create more impact.

Render of the bottom

Step 3

In the chest, there are different types of treasure, and we will render them separately, but do not forget to add reflections to blend them together better. So, for gold, add more shadows for depth and hide the contours. For the diamonds, we add some highlights to make them look as if they're shining.

Render of the gold

Step 4

A pearl has the simple shape of a sphere, so you draw it using the same rules. Three basic colors will be enough: one middle tone, one for lights, and one for shadows, according to the light source.

Take the Air Brush and begin to apply the colors, moving smoothly. To blend colors better, use Water or Blur brushes.

Progress of the pearl

Step 5

To draw other pearls faster, we'll use a simple trick. As soon as you've made one whole pearl, just copy it and paste it in the places of the other pearls. Adjust their sizes according to the line art. 

You'll notice that these new pearls look separate from the rest of the image, so we need to fix that. To blend them out more smoothly, we'll add reflections from the nearby objects and more shadows, and we'll cover their outlines.

Render of the pearls

Step 6

And we're ready! But right now our treasure chest looks a bit blurry and doesn't have enough contrast, so let's work more on that.

Finished render

6. Color Adjustment of the Treasure Chest

Step 1

To begin, create a New Layer on top of all other layers and set its Mode to Overlay with 70% opacity. Use soft colors to add vibrancy to the picture. Experiment with different colors to achieve the best effect.

Adding overlay layer

Step 2

With our next step, we'll lighten up the parts where the light source falls directly. Create a New Layer on top of the others and set its Mode to Luminosity. Take white or a soft yellow color and apply it to the most well-lit parts of the chest and treasure. Then set the mode of the layer to 20% opacity.

Adding highlights

Step 3

The next step will be about applying Paint Tool SAI filters. And the first filter we'll use here is changing the Hue and Saturation. So you can easily adjust the colors on your drawing just by playing with these options. Make sure that Preview is on, so you'll see the changes immediately. 

Experiment with the settings or just add +15 to the Saturation. It will add more vibrancy to the colors.

Adjusting hue and saturation

Step 4

The second filter will change the Brightness and Contrast of the drawing. Once again, you can experiment with the settings or use these: Brightness +20, Contrast +15, Color Deepen +15.

Adjusting brightness and contrast

Awesome Work! You've Made It!

You've made it and hopefully learnt some new techniques of drawing in Paint Tool SAI. This process of work is pretty straightforward and easy to use, and will definitely help you in future illustrations.

Share your results, and have fun creating!

Finished illustration
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