How to Invert a Colour

How do I invert a colour?

It depends on what do you mean by "inverting" a color

Your code provides a "negative" color.

Are you looking for transform red in cyan, green in purple, blue in yellow (and so on) ? If so, you need to convert your RGB color in HSV mode (you will find here to make the transformation).

Then you just need to invert the Hue value (change Hue by 360-Hue) and convert back to RGB mode.

EDIT: as Alex Semeniuk has mentioned, changing Hue by (Hue + 180) % 360 is a better solution (it does not invert the Hue, but find the opposite color on the color circle)

How to invert an RGB color in integer form?

I think it is so simple.
You can just calculate 0xFFFFFF-YourColor. It will be the inverted color.

int neg = 0xFFFFFF - originalRGB

// optional: set alpha to 255:
int neg = (0xFFFFFF - originalRGB) | 0xFF000000;

How to invert texture colours in OpenGL

Its s simple as

gl_FragColor = vec4(1.0 - textureColor.r,1.0 -textureColor.g,1.0 -textureColor.b,1)
It is best to do this kind of thing in the shader, if you want to do it once and then reuse it for future draws just use render to texture. This is the fastest way to do color inversion.

EDIT: You use
vec4 textureColor = texture2D(uSampler,vTexCoords)
before your do gl_FragColor
using .r ,.g,.b and .a access the red, green, blue and alpha values respectively.

How to invert colors in LESS

There are multiple interpretation of inverting color.

You want a color with the opposite hue:
spin(@color, 180)
You want a color that the sum with current one is white:
#fff - @color

Invert color of a page

Your solution:

document.body.style.filer = "invert(100%)";
Object.values(document.body.getElementsByTagName("*")).forEach(e => {
    e.style.filter = "invert(100%)"
});

didn't really work because you're inverting colours from parent elements and their children. Inverting twice causes the element to have the original colour. Therefore, you only need to invert the colour of the parent(s) (in this case, the html, which is the root of everything):

document.querySelector('html').style.filter = 'invert(100%)'

And every colour will be inverted. Note that if you try to use this on a colourless element, nothing will change, i.e. if you try this script on this page, you will notice that the div on the left side of this page with the id left-sidebar will not change in colour. This is due to the sidebar not having any colour (the middle section and right sidebar is inverted because they're inside the div#content which has white background colour).

However, if you add background (e.g. white) to the left side bar, it will also invert its colour.

How can I invert color using CSS?

Add the same color of the background to the paragraph and then invert with CSS:

div {    background-color: #f00;}
p {     color: #f00;    -webkit-filter: invert(100%);    filter: invert(100%);}

<div>    <p>inverted color</p></div>

How to invert color of entire page when hovering on a link

You have to use Javascript to achieve what you want.
The idea is to apply a class with filter: invert(1); to the body element when the mouse is over (onmouseoover event) the link and remove it when the mouse leaves (onmouseleave event):

const invertLink = document.querySelector('#invert');const toggleDark = () => document.querySelector('body').classList.toggle('dark');invertLink.addEventListener('mouseover', toggleDark);invertLink.addEventListener('mouseleave', toggleDark);

.dark {  filter: invert(1);  background: black;}

<body>  <h1>Hello World</h1>  <a href="#" id="invert">Hover me!</a><br><br>  <img src="https://www.gravatar.com/avatar/"></body>

how do you invert a color in flutter?

As per http://www.vb-helper.com/howto_invert_color.html:

You can invert a color by subtracting each of its red, green, and blue
components from 255. In other words:
new_red   = 255 - old_red
new_green = 255 - old_green
new_blue  = 255 - old_blue

Color invert(Color color) {
  final r = 255 - color.red;
  final g = 255 - color.green;
  final b = 255 - color.blue;

  return Color.fromARGB((color.opacity * 255).round(), r, g, b);
}

void main() {
  final inverted = invert(Colors.deepOrange);
}

Algorithm for calculating inverse color

newR = 1.0 - r
newG = 1.0 - g
newB = 1.0 - b

If the color has a premultiplied Alpha value use the alpha instead of 1.0:

newR = a - r
newG = a - g
newB = a - b

How to invert color of seaborn heatmap colorbar

The default cmap is sns.cm.rocket. To reverse it set cmap to sns.cm.rocket_r

Using your code:

cmap = sns.cm.rocket_r

ax = sns.heatmap(cm_prob,
                 annot=False,
                 fmt=".3f",
                 xticklabels=print_categories,
                 yticklabels=print_categories,
                 vmin=-0.05,
                 cmap = cmap)