In Part 1 of this two part tutorial series, we learned how to code a script which converts a flat process color into its matching gradient. In this tutorial, we will learn to code a script that converts a gradient fill into a flat process color. We will melt the available gradient color into a flat process color, which will be a mixture of all the colors available in that gradient.

This entire task will be performed via JavaScript script for Illustrator. The tutorial assumes that you’re familiar with the basics of scripting. For those who’ve directly landed on this tutorial, we have a little know-how covered about Illustrator’s Javascripts in Part 1 of this series. So without further delays, let’s get started!

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Tutorial Details

• Program: Adobe Illustrator and ExtendedScript Toolkit
• Version: CS3
• Difficulty: Intermediate
• Estimated Completion Time: 3 to 4 Hrs

Purpose of the Script

We want this script to perform a very simple task. In Adobe Illustrator, when a user selects some objects filled with a CMYK Gradient Color, and executes this Script; the objects shall get converted into a Flat CMYK fill. This flat fill will be the mixture of all the colors available in the former gradient. See the image below for clarification.

Hence, the aim of our script is to convert a Gradient CMYK Fill into a Flat CMYK Fill.

Logic and Algorithm

The logic for melting the colors of a gradient into a single color is simple and straightforward. We’ll pick all the colors from the gradient, find their average and assign it to the object as a new color. We can understand this in five steps, as shown below:

• Step 1: Pick the color of the current object. i.e. currentColor = color of currently selected object.
• Step 2: Count the number of gradient stops in the current color.
• Step 3: At each gradient stop, pick the associated color and its CMYK values.
• Step 4: Calculate the average CMYK value for all colors available at different stops.
• Step 5:
  Assign this average CMYK value as a new color to the object.

The above algorithm can be easily understood from the pictorial representation below.

We have seen a brief overview of the logic. Let’s get started with the coding.

Step 1 – Starting with the Code Structure

Open ExtendedScript Toolkit and create a new Javascript file (Command + N). Next, select Adobe Illustrator for the target application.

In the code editing area, add the following code structure for certain validations and pre-requisite checks.

if ( app.documents.length > 0 && app.activeDocument.pathItems.length > 0) { if(app.activeDocument.documentColorSpace == DocumentColorSpace.CMYK) { convertToFlat(); } else { alert("Convert the Objects into CMYK First", "CMYK Conversion required"); } }//end main if

else { alert("Either no document is available or the document is empty"); } 

We are checking if at least one document with at least one object exists, so that we can work upon it. Next, we are checking whether the document color mode is CMYK or not. This is an essential step because all the logic for color conversion in this script is based upon CMYK colors. convertToFlat() is the main function which will contain all the logic. Next, save this file as test.jsx.

Step 2

Let’s now start with the main function – convertToFlat(). We’ll check if any item is selected or not, because this script will work on the selected objects only. Hence, add the following lines of code to “test.jsx.”

function convertToFlat() {

var items = selection; var totalSelected = items.length;

if(totalSelected > 0) { // proceed with the main logic }

else { alert("Please select atleast one object"); }

}//end convertToGrad 

Step 3

Next, we will start a loop inside the “if(totalSelected > 0)” block. This loop will contain the color conversion logic, which is repeated for each selected item. But just before the color conversion logic, let’s add some more validations and checks inside that loop.

    if(totalSelected > 0) {

for(var j=0; j < totalSelected; j++) { var currentObject = app.activeDocument.selection[j];

if(currentObject.typename != "CompoundPathItem" && currentObject.typename != "GroupItem") { if(currentObject.filled==true && currentObject.fillColor.typename != "CMYKColor" && currentObject.fillColor.typename != "PatternColor" && currentObject.fillColor.typename != "SpotColor") {

// Color conversion Block

} //endif

else { alert("Fill an object with CMYK or Grayscale Gradient. Flat Colors, Patterns, Spot Colors and Empty Fills are not allowed."," Only Gradients Allowed"); } } //endif

else { alert("This script only works with Non-Compound Objects or Isolated Group items.nAny items with Groups or Compound Objects will be omitted.", "Ungroup or Isolate the Group Items"); }

}//endfor

}// endif 

For each selected item, we are checking whether it is a Compound Path or a Group Item. If so, the script shall not execute anymore and return an alert message. Further, we are checking if the fill-type of the selected item is something other than Gradient Fill. i.e. If it is a spot color, flat CMYK color or a pattern; the script shall return an alert. These checks are performed because our script will only work for gradient filled non-compound path items.
Next, we will modify the Color conversion Block.

Step 4

At this stage, we need to extract individual C, M, Y and K values for the colors residing at different gradient stops. For that, we will create some variables which will hold individual CMYK values. So, add the following variable declarations just inside the Color conversion block:

        var currentColor = currentObject.fillColor; var numOfStops = currentColor.gradient.gradientStops.length; var colorBox=[]; var cyanBox=[]; var magentaBox=[]; var yellowBox=[]; var blackBox=[]; var grayBox =[]; var cyanTotal = 0; var magentaTotal = 0; var yellowTotal = 0; var blackTotal = 0; var grayTotal = 0; 

We will see the role of each variable one-by-one:

• currentColor will store the fill color (gradient) of the currently selected object.
• numOfStops contains the total number of gradient stops available in currently selected object. This will be used to find the average of color values in later stages.
• colorBox is an array which will hold the fill-color value for all the gradient stops. i.e. if numOfStops is four.
• colorBox array will contain four colors.
• cyanBox is an array which holds cyan values for each color on different gradient stops.
• Similarly, magentaBox, yellowBox and
  blackBox hold their respective color values for each color on different gradient stops.
• grayBox is an array which holds gray values for the color on any gradient stop. This is essential because the gray color is a different specification than CMYK color specification. In case, an object contains a gray gradient, we will handle the situation separately by making use of this variable.
• Finally, we have cyanTotal, magentaTotal, yellowTotal, blackTotal and grayTotal. These variables contain the summation of all the cyan, magenta, yellow, black or gray values respectively.

Step 5

We have performed the validations and checks. We have also created necessary containers to hold color values. Next, we will run a loop which reads each gradient stop one-by-one. For that, create a loop, as shown below:

    for(var k=0; k < numOfStops; k++) { colorBox[k] = currentColor.gradient.gradientStops[k].color; if(colorBox[k].typename == "GrayColor") {

// Extract Gray Color values

}

else {

// Extract CMYK Color values

}

}//end for k 

currentColor.gradient.gradientStops[k].color returns the color of a particular gradient stop for each iteration of k.

For each gradient stop, we are checking if the available color is a GrayColor specification or a CMYKColor specification. Depending upon that, we will implement our logic.

Step 6 – Summation of GrayColor Values

Inside the "if block" for GrayColor specification, add the following lines of code:

    grayBox[k] = Math.round(colorBox[k].gray); grayTotal = grayTotal + grayBox[k]; 

Hence, grayBox[k] will hold all the gray values for each color at their respective gradient stops.
Next, grayTotal will be the summation of these gray color values, which will be used later.

Step 7 – Summation of CMYK Color values

Inside the "else block" for CMYKColor specification, add the following lines of code:

    cyanBox[k] = Math.round(colorBox[k].cyan); magentaBox[k] = Math.round(colorBox[k].magenta); yellowBox[k] = Math.round(colorBox[k].yellow); blackBox[k] = Math.round(colorBox[k].black);

cyanTotal = cyanTotal + cyanBox[k]; magentaTotal = magentaTotal + magentaBox[k]; yellowTotal = yellowTotal + yellowBox[k]; blackTotal = blackTotal + blackBox[k]; 

To understand what is being performed here, we will take an example of Cyan color. cyanBox[k] is storing the cyan values for all the colors residing at different gradient stops. Next, cyanTotal is the summation of all these cyan values that are stored in cyanBox[k].

A similar operation is performed for magenta, yellow and black too. Once the summation is done, we can come out of the loop and proceed ahead for average.

Step 8 – Averaging the Color Values

We have gathered the individual summation of grayColor and CMYKColor for all the gradient stops. Now we need to average them. For that, close the "for k loop" and enter the following lines of code just after the closing bracelet of "for k loop", as shown below:

    } // end for k loop

var finalBlack = blackTotal + grayTotal;

var newCyan = Math.round(cyanTotal / numOfStops); var newMagenta = Math.round(magentaTotal / numOfStops); var newYellow = Math.round(yellowTotal / numOfStops); var newBlack = Math.round(finalBlack / numOfStops); 

In the above lines of code, we are dividing individual summations of C, M, Y and K by numOfStops. i.e. If there were five gradient stops, we will divide the summation of individual C, M, Y and K values with five. Thereby, returning an average of five values. These averaged values are stored as newCyan, newMagenta, newYellow and newBlack respectively.

Note the tricky case of gray and black here. The summation of K is not just blackTotal. Rather, it's a sum of grayTotal and blackTotal.

Why we have done that? There are cases when a gradient fill may contain both GrayColor stops and CMYK stops. In that case, the gray Color values are added to the K value of the CMYK color. Gray can not be added to cyan, magenta or yellow. It will fall in the category of K only.

Now we have all the new averaged values for C, M, Y and K in hand. In the next step, we will implement these values as a new CMYK color on the current object.

Step 9 – Implementing the New Color

To implement the new color, we will create a new CMYKColor object and modify its C, M, Y and K values to the ones that we just calculated in Step 7. To do that, add the following lines of code:

    var newColor = new CMYKColor();

newColor.cyan = newCyan; newColor.magenta = newMagenta; newColor.yellow = newYellow; newColor.black = newBlack;

currentObject.fillColor = newColor; 

We have created a newColor object and assigned the values of newCyan, newMagenta, newYellow and newBlack as its C, M, Y and K values respectively.

Continue Learning…

The gradient mesh is one of the most powerful tools in your Illustrator toolbox, but it’s also one of the trickiest to get the hang of. This year I’m determined to master this amazing tool, so I’ve searched the web far and wide to pull together the best free training materials. This collection of tutorials covers everything from basic gradient mesh tool to some full on photorealistic vector designs. If, like me you have a mission to get to grips with gradient mesh, look no further than this collection of resources.

Gradient mesh capabilities

You only have to glance at amazing artwork such as this motorcycle rendering by Yukio Miyamoto to realise how powerful the gradient mesh tool can be. It allows the most minute control over colour gradients, enabling you to recreate highlights and shadows that help produce photorealistic images.

I like to think of the gradient mesh like the great Nunchaku, it’s a weapon of awesome capabilities that when used to its full potential by masters like Bruce Lee or Michelangelo the turtle looks insanely awesome. However it takes years of practice to become a true ninja. The same goes with the gradient mesh, when in the hands of a veteran, it can be used to create some unbelieveable photorealistic artwork, but it takes time, dedication and mental power to become a true master. Wrap a scarf around your head Karate Kid style and let’s get down to some serious training with these tutorials!

Gradient mesh tutorials

Tips for Working with the Gradient Mesh Tool In Illustrator

How to Make a Vector Military Cap Icon

Illustrator Tutorial: Gradient Mesh Flower

Create a Yummy Ice Cream Icon with Mesh Objects and Blends

Create realistic illustrations using Illustrator’s Gradient Mesh

Vectors Imitate Life with Gradient Mesh

Gradient Mesh Tutorial

Illustrate a Pair of Sweet Gradient Mesh Cherries

Gradient Mesh Bell Pepper Tutorial

Master the gradient mesh tool

Make a Shiny Gum Ball Machine with Mesh Gradients

Gradient Mesh Editing Tutorial

How to Create an Energy Saving Bulb in Illustrator

Mastering Mesh

Make an Aurora Borealis Design in Illustrator

Illustrator Tutorial: Realistic Curtain

Video Tutorials

Sometimes it’s handy to get that extra level of help from a video screencast. These tutorials help you understand the actual workflow and see the techniques in action.

Read More…

In this tutorial, we'll explain how to create a flower with Illustrator’s mesh tools and opacity masks. With these tools you have a high-degree of control and can create realistic looking illustrations. Let’s get started!

Final Image Preview

Below is the final image we will be working towards. Want access to the full Vector Source files and downloadable copies of every tutorial, including this one? Join Vector Plus for just 9$ a month.

Tutorial Details

• Program: Adobe Illustrator
• Version: CS4
• Difficulty: Intermediate
• Estimated Completion Time: 1.5 hours

Step 1

Open up a new document and select the Polygon Tool. Click once on the artboard and choose Radius 50pt and Sides: 6 in the pop up window. Fill the polygon with an orange color.

Step 2

Select the Mesh Tool (U) and start adding mesh points. Click once on the top line of the polygon.

Step 3

Then repeat the step by clicking in the middle and on the right of the top horizontal line of the polygon as shown.

Step 4

Then click once right into the middle of the polygon with the Mesh Tool (U).

Step 5

Select the Direct selection Tool (A) and highlight the center mesh point, then fill it with a darker orange.

Step 6

Next, select each corner mesh point and fill it with a yellow.

Step 7

Start dragging each middle mesh point of each side of the polygon towards the middle until you create a similar star shape, just like you see in the image below.

Step 8

Let’s move onto the flower pedal creation. Select the Pen Tool (P) and draw a similar shape as shown in the image below. Fill it with 5% Black.

Step 9

Create another shape similar to the one shown below, which will be the bottom part of the flower pedal. Fill it with a pink or any other color of your choice. Then go to Effect > Stylize > Feather, then set the Feather amount to 5pt. Place it on top of the gray pedal.

Step 10

Apply mesh points to the pedal with the Mesh Tool (U). Select random mesh points and fill them with a darker gray.

Step 11

Select the smaller pink shape and make a copy. Then scale it down to about 75% of the original one. Fill it with a darker pink or a purple. Apply a Feather effect of 2pt.

Step 12

Group the flower pedal and the two small shapes together. Then select the grouped shape and Rotate (R) and duplicate it until you have six pedals.

Click for full Tutorial…