Wave Animation 2D Using the Grease Pencil in Blender

Today we’ll be drawing and animating in 2D in Blender using the Grease Pencil tool. In this project I’ll be using the 2.93 version of Blender.

So, let’s get started. Here are the steps to follow:

Step 1 – Create a New 2D Animation File

We’ll start with the splash screen today. If you just launched Blender, you will see the splash screen right away. You can create a new 2D Animation file by choosing the appropriate option there.

But if you already closed the splash screen, you can still create a new file from the File menu by selecting 2D Animation under New:

Make sure to save the file right away.

Step 2 – Use the Grease Pencil to Draw Some Lines

As soon as the new file is created, you’re ready to draw. The Grease Pencil object that you can use to draw is already there. You can see it in the Outliner. It’s called Stroke:

So, just drag your mouse over the white canvas and draw something:

Step 3 – Display the Names of the Drawing Tools

You can use some pretty handy tools to draw with the grease pencil. The toolbar is on the left:

Hover your mouse over the right border of the toolbar and drag to the right. This way you will expand the toolbar and you will see the names of the tools:

Step 4 – Erase the Drawing

Before we start work on our actual drawing, let’s erase the one we just drew. To do that select the Erase tool (A) from the toolbar, increase the radius of the eraser if necessary (B) and erase everything (C):

Step 5 – Change the Brush

Now, before we start drawing the waves, let’s make sure we’re on the Lines layer (A). Let’s also make sure we’re at frame 1 (B). Select the Draw tool (C). And one more thing, the brush. We want to change it to Pen, so click on the Brush dropdown (D) and select Pen (E):

Step 6 – Draw a Line using the Curve Tool

We’re going to use the Curve tool, so just select it in the toolbar (A). Zoom out a bit by scrolling the scroll wheel on your mouse. Now draw a short line near the bottom left corner. Hold down Shift while doing it so that the line is constrained to horizontal direction (B):

Step 7 – Shape a Single Wave

Drag the two blue handles on the line to shape a single wave:

Step 8 – Confirm the Operation

Hit Enter to confirm the drawing operation. Now we have a single wave:

Step 9 – Add an Array Modifier

We need the whole ocean, not just a single wave, so let’s add an array modifier. To do so, go to the Modifiers tab (A) and select the Array Modifier (B). Now you can see two waves separated from each other.

We want the single waves to be connected in horizontal direction. To do that make sure the Relative Offset checkbox (C) is checked. Then type in the value of the offset in the Factor X slot (D). This number may be different for you, depending on how long your single wave is. In my example it’s 0.69. Anyway, make sure the waves are connected smoothly without any gaps between them.

Depending on how long your single wave is, you may need a different number of single waves to form the first row of waves. Just set the Count value (E) to this number. In my example it’s 6 waves.

Step 10 – Apply the Array Modifier

Now we’re going to apply the modifier, but to do that we must be in object mode (A). Deselect all and then click on the dropdown (B) in the Modifiers tab and click Apply (C).

Step 11 – Close the Wave Curve

Let’s close the wave so that we can later fill it with a color. First, go to edit mode, select all and move the wave up by hitting G Z 1.

This will give us more room to work. Go back to Draw mode. Now select the Polyline tool (A) and draw a line that consists of three segments. The first segment should start near the left side of the wave and slightly above it. Start drawing and hold down the Shift key so that the segment remains vertical. When you’re near the bottom of the canvas, left-click to finish the first segment and then immediately draw the second segment from left to right. Also hold down the Shift key to make it horizontal. Repeat the steps to draw the third vertical segment on the right. Make sure the wave and the polyline make a closed shape.

Step 12 – Fill the Row of Waves with a Color

Now we’re ready to fill the waves with colors. There are going to be more rows of waves soon. Let’s make each row of waves a slightly different color. Let’s start with the only row we have, though. Select the Stroke object in the Outliner (A). Select the Fill tool (B) and in the Dope Sheet select the Fills layer (C). Go to the Material tab (D), select one of the preset fill materials, like for example Solid Fill (E) and set the Base Color to a shade of blue or green (F). Make sure the Fill checkbox is checked (G) and the Stroke checkbox is unchecked (H). Then hover your mouse cursor over the closed wave shape and left-click to add the color (I).

Rename the material ‘waves1’:

Step 13 – Add More Waves

Now we have a single row of waves. But we want more of them, like five, so let’s add them now one by one. Go to object mode and select the Stroke object in the Outliner. Hit Shift + D to duplicate the first row of waves and then immediately Z .5 to move it up. Then hit G X .2 to move it slightly to the right.

It’s a good time to rename our strokes. Rename the first one ‘waves1’ and the second one ‘waves2’.

Let’s add a new material for the second row of waves. Go to the Material tab. Hit the button with the plus sign on it to add a new material slot:

And then hit the New button to add a new material. Rename the material ‘waves2’ (A). Check the Fill checkbox (B) and uncheck the Stroke checkbox above (C). Then set the Base Color (D). You can choose any shade of blue or green you like. Finally, go to draw mode, select the Fill tool and fill the second row of waves with the new color (E):

Go to object mode, select the first row of waves and duplicate it. Move it up (Z 1) and to the left (G X -.1).

Then select the second row and duplicate it. Move it up (Z 1) and to the right (G X .1).

Finally, select the third row and duplicate it. Move it up (Z 1) and to the left (G X -.1)

In the Outliner rename the new rows of waves ‘waves3’, ‘waves4’ and ‘waves5’.

We’re done with the waves for now. Let’s now draw the mermaid.

Step 14 – Add Another Stroke

We’ll also draw a mermaid that will jump out of the ocean, over the waves and back into the ocean. Let’s create a new stroke object. So, make sure you’re still in object mode and add a new stroke by hitting Shift + A and then selecting Stroke under Grease Pencil. You will see some basic shape appear (A). The new stroke will also appear in the Outliner. Rename it ‘mermaid’ (B). As you can see near the bottom of the screen, now we can see the Dope Sheet for this particular stroke (C):

Step 15 – Delete the Points

We want to create the mermaid from scratch, so let’s go to edit mode (A), select all and hit X and then Points (B) to delete the points that we got when creating the stroke:

Step 16 – Draw the Mermaid

Go to draw mode (A), make sure you’re on the Lines layer (B) and at frame 1(C). Select the Draw tool (D) that will let you draw freehand and draw a mermaid (E). Yours doesn’t have to be as perfect as mine.

Step 17 – Move the Mermaid Down

Let’s move the mermaid to the position she will start at. To do that we must be in object mode. Select the mermaid and move it down so that her head is below the two upper rows of waves:

Step 18 – Create a Wave Collection

Now we have the mermaid and five waves. Let’s move the waves to a separate collection. First right-click on Scene Collection in the Outliner and select New Collection.

Rename the new collection ‘waves’ and move the five wave objects into it. To do that just select all of them and drag them into the collection.

Step 19 – Fill the Mermaid with Colors

Now we can fill the mermaid. In order to better see the mermaid and get the waves out of the way, let’s temporarily hide them. Click on the little eye icon next to the waves collection in the Outliner to hide everything inside the collection.

Select the mermaid and zoom in to see her better. Go to draw mode (A), select the Fill tool (B) and in the Dope Sheet select the Colors layer (C). Go to the Material tab and click the plus sign (D) to add a new material slot and then the New button to add a new material. Rename the material ‘mermaid1’ (E) and set the Base color (F) to any color you like. Make sure the Fill checkbox is checked (G) and the Stroke checkbox is unchecked (H). Then fill the body and tail of the mermaid with it (I):

Next add as many materials as you like to fill the other parts of the mermaid’s body. You can name them simply ‘mermaid2’, ‘mermaid3’, etc. (A). Make sure that for each material the Fill checkbox is checked (B) and the Stroke checkbox is unchecked (C). Set the colors to your liking and fill the mermaid. This is what I ended up with:

Step 20 – Merge the Layers

Now the lines and the fills are on two separate layers. Let’s merge them together. To do that go to the Object Data tab (A) and there, under Layers, you will see the same two layers as in the Dope Sheet. Select the Lines layer (B). Click on the dropdown button (C) and select Merge Down (D):

Now we have just one layer. It’s named just like the second layer before, so let’s change it to something more meaningful like ‘mermaid’ (A). You will see the new name in the Dope Sheet as well (B):

Step 21 – Merge Down the Layers of the Waves

Now that we’re done with the mermaid, you can unhide the waves by clicking on the eye icon again:

Just like we did with the mermaid, let’s merge the layers of the waves. Go to object mode and select each wave object one by one. Then, in the Object Data tab select the Lines layer, expand the dropdown and select Merge Down. You can rename the new layer ‘waves’.

Step 22 – Start the Wave Animation

We want the waves to be animated. They will just slide from left to right and back. We’re going to animate particular rows of waves. Make sure you’re in object mode.

Our animation is going to last 10 seconds, which means we need 240 frames as it’s going to be played at 24 frames per second. So, switch from the Dope Sheet editor to the Timeline editor (A) and set the end frame to 240 (B). Make sure Auto Keying is on so that the keyframes are added automatically any time a value changes (C).

Make sure you’re still at frame 1. As we haven’t changed the position of the first row of waves, there are probably no keyframes at frame 1 for this row. To fix this, select the waves1 object (A) and hit I to add a keyframe. Select Location, Rotation & Scale (B).

This will add the keyframe at frame 1. There already should be keyframes for the other rows of waves, provided Auto Keying was on all the time. To make sure, just select waves2, waves3, waves4 and waves5 one by one and see whether they are keyframed. If not, just add the keyframes like for waves1.

Let’s create two sliding cycles, each cycle consisting of the movement in one direction and back. We want one single sliding cycle to be 5 seconds long, so after 2.5 seconds the waves should change direction. This means we need to insert keyframes at the frames where the waves should change direction. These are frames 61, 121 and 181 (because 60 frames are played in 2.5 seconds at 24 fps).

Let’s start with frame 61. Go to this frame (A). Then select the odd rows of waves, so row 1, 3 and 5 (B):

Move the selected waves along the X axis to the right (G X .4). When you move the selected parts, a new keyframe will be inserted at frame 61.

Still at frame 61 deselect the waves and select the two even rows, so waves2 and waves4.

Now move the selected rows of waves along the X axis to the left, but just a little bit (G X -.1). We want these two rows of waves to move more slowly. The keyframes will be added automatically.

Step 23 – Duplicate Keyframes

Select all the waves. If you now go to frame 1 and play the animation, it will play for the first 2.5 seconds as expected. The waves will move to their target positions, but then they should turn back and move to their original positions. Then the cycle should be repeated. Let’s do that now. In the Timeline make sure only the first keyframe is selected.

Duplicate the keyframe by hitting Shift + D and move it to frame 121. Then duplicate again and move to frame 240. Next, select the keyframe at frame 61, duplicate and move to frame 181:

Play the animation to make sure it works as expected.  We’re done with the waves animation. Now let’s animate the mermaid.

Step 24 – Plan the Mermaid Animation

First of all go to object mode and select the mermaid in the Outliner (A). To make sure she’s behind the waves, hit N to open the sidebar and set the Y position to .1 (B). The Y position of the waves is 0, so the mermaid will be placed in the back.

Now let’s think about how we want the mermaid to be animated. As you can see, it’s now hidden behind the waves on the right side of the screen. Let’s make it jump over the water three times, each time in a greater distance. So, first it will jump from right to left, then from left to right and one more time from right to left.

The whole animation takes 10 seconds. Let’s plan it out then:

3 seconds (frames 0 – 72): just the waves animation

1.5 seconds (frames 73 – 108): first jump (from right to left, in near distance)

1 second (frames 109 – 132): just the waves animation

1.5 seconds (frames 133 – 168): second jump (from left to right, in a further distance)

1 second (frames 169 – 192): just the waves animation

1 second (frames 193 – 216): third jump (from right to left, in the maximum distance)

1 second (frames 217 – 240): just the waves animation

So now we know where the keyframes should be. But what exactly do we want to animate? First of all, the mermaid’s position, but also its rotation.

Each jump over the water must be divided into two parts: first the mermaid must move up to her maximum height where she’s positioned horizontally, and then she must move down into the water, with her head pointing down. The mermaid must also flip horizontally between jumps, which we can accomplish by scaling it by a factor of -1 on the X axis.

So, if we consider this, we can rewrite our keyframe plan like so:

second 0 / frame 0: mermaid at its original location

second 3 / frame 72: mermaid still at its original location

second 3.75 / frame 90: mermaid at maximum height, in horizontal position, heading left

second 4.5 / frame 108: mermaid under water on the left, at maximum rotation to the left

second 5.5 / frame 132: mermaid under water on the left at original rotation, flipped horizontally and further away on the Y axis (we don’t see this part of the animation)

second 6.25 / frame 150: mermaid at maximum height, in horizontal position, heading right

second 7 / frame 168: mermaid under water on the right, at maximum rotation to the right

second 8 / frame 192: mermaid under water on the right at original rotation, flipped horizontally and further away on the Y axis (again, we don’t see this part of the animation)

second 8.5 / frame 204: mermaid at maximum height, in horizontal position, heading left

second 9 / frame 216: mermaid under water on the left, at maximum rotation to the left

second 10 / frame 240: mermaid still under water on the left, at maximum rotation to the left (we don’t need a keyframe here)

Now we are ready to implement the animation:

Step 25 – Animate the Mermaid

The origin of the mermaid is probably outside its geometry. To fix this, select the mermaid and in the Object menu, under Set Origin select Origin to Geometry. Now it will be much easier to handle the location and rotation of the mermaid.

With the mermaid animation plan in place, we can now add all the keyframes we need. As Auto Keying is on, we already have a keyframe at frame 1. But the mermaid is now where the origin used to be, so move her to the position you want her to start at, which is on the right.

Let’s duplicate it and move the duplicate to frame 72 (A). Next, let’s move on to frame 90 (B). Now the mermaid should be at her maximum height and rotated so that she’s in horizontal position, heading left. So, move the mermaid and rotate her like accordingly (C). The keyframe will be added automatically.

Then go to frame 108 (A) and move the mermaid down and to the left. Rotate her so that her tail is above her head (B).

Go to frame 132 (A) and rotate the mermaid so that her rotation is more or less like at the beginning of the animation. Then hit S X -1 to flip her horizontally (B).

Next, go to frame 150 (A) and move the mermaid up. Rotate her so that she is in horizontal position, heading right (B). In the sidebar set the Y location to 5 (C). This will move the mermaid away from you into the sea:

Next, go to frame 168 (A). Move the mermaid down and to the right. Rotate her so that her tail is above her head again (B).

Next, move on to frame 192 (A) and rotate the mermaid so that her rotation is more or less like at the beginning of the animation again, just facing the opposite direction. Then hit S X -1 to flip her horizontally (B). In the sidebar set the Y location to 15 (C). This will move the mermaid even further away from you into the sea.

Now go to frame 204 (A). Move the mermaid up and rotate her so that she’s in horizontal position, heading left (B):

Next, go to frame 216 (A). Rotate the mermaid again so that her head is below her tail and move her down and to the left (B):

Go back to frame 1 and play the animation to make sure it works.

Step 26 – Align the Camera

Now let’s align the camera so that it can see only the part of the scene that we want to be rendered. In the sidebar go to the View tab (A) and under View Lock check the Lock Camera to View option (B). Now go to a frame where the mermaid is near its extreme position, which is frame 90 (C), and zoom in and pan so that she can be still fully visible inside the camera view (D):

Step 27 – Render the Animation

Uncheck the Lock Camera to View checkbox and hit N to close the sidebar. We’re almost ready to render the animation. Go to the Output tab (A) and select a folder where you want to save the animation (B). Set the file format to FFmpeg video (C) and under Encoding select the MPEG-4 container (D):

Under Render select Render Image to make a test render. You should see something like this:

Close the window. Finally, under Render select Render Animation. It will take some time to complete, but not too long.