[Docs] - How to work with colors in shaders (#9)

COLORS.md

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+# Colors
+
+## Flutter Colors
+
+The Color Class in Flutter is a immutable 32 bit color value, with four channels. These channels are namely Alpha, Red, Green and Blue.
+
+Each channel are represented by two hexadecimal numbers, that can represent 255 different values.
+
+    Color(0xAARRGGBB)
+
+AA, returns a color that matches the alpha cannel with a Hexadecimal value.(value between 00 and FF)
+
+RR, returns a color that matches the red cannel with a Hexadecimal value.(value between 00 and FF)
+
+GG, returns a color that matches the green cannel with a Hexadecimal value.(value between 00 and FF)
+
+BB, returns a color that matches the blue cannel with a Hexadecimal value.(value between 00 and FF)
+
+## Conversion from Hexadecimal color to Decimal Color
+
+If we consider the Color(0xFF448AFF), we can deduct the following from each channel.
+
+Alpha - FF represents this channel - if we convert the hexadecimal to decimal.
+
+    (FF)₁₆ = (15 × 16¹) + (15 × 16⁰)  = (255)₁₀
+
+Red - 44 represent this channel - if we convert the hexadecimal to decimal.
+
+    (44)₁₆ = (4 × 16¹) + (4 × 16⁰) = (68)₁₀
+
+Green - 8A represent this channel - if we convert the hexadecimal to decimal.
+
+    (8A)₁₆ = (8 × 16¹) + (10 × 16⁰) = (138)₁₀
+
+Blue - FF represent this channel - if we convert the hexadecimal to decimal.
+
+    (FF)₁₆ = (15 × 16¹) + (15 × 16⁰)  = (255)₁₀
+
+Now from our calculations above we can conclude that Color(0xFF448AFF) can be represented as Color.fromARGB(255, 68, 138, 255).
+
+## GLSL color
+
+In OpenGL Shading Language colors can be stored in floating-point vector variables. For this e use a vec4 myRGBA.
+
+The vec4 using an array of four-component unsigned integer vector.
+
+    vec(r.r, g.g, b.b, a.a)
+
+r.r, returns a color that matches the red cannel with a floating-point vector value.(value between 0.0 and 1.0)
+
+g.g, returns a color that matches the green cannel with a floating-point vector value.(value between 0.0 and 1.0)
+
+b.b, returns a color that matches the blue cannel with a floating-point vector value.(value between 0.0 and 1.0)
+
+a.a, returns a color that matches the alpha cannel with a floating-point vector value.(value between 0.0 and 1.0)
+
+Ref
+https://registry.khronos.org/OpenGL/specs/gl/GLSLangSpec.4.40.pdf
+
+
+## Converting for Hexadecimal color to vec4 Floating point color 
+
+Converting decimal numbers to floating-point the decimal value are divided by 255.
+
+If we consider the Color(0xFF448AFF) can be represented as Color.fromARGB(255, 68, 138, 255) (rom calculation above) we can deduct the following for each channel
+
+Alpah  - 255 represents this channel - if we convert the decimal to floating-point.
+
+    255 / 255 = 1.0
+
+Red  - 68 represents this channel - if we convert the decimal to floating-point.
+
+    68 / 255 = 0,2667
+
+Green  - 138 represents this channel - if we convert the decimal to floating-point.
+
+    138 / 255 = 0,5412
+
+Blue  - 255 represents this channel - if we convert the decimal to floating-point.
+
+    255 / 255 = 1.0
+
+Now from our calculations above we can conclude that Color(0xFF448AFF) can be represented as vec4(0,2667, 0,5412, 1.0, 1.0).
+
+![Hex_GLSL_colour.png](https://github.com/Flutter-Bounty-Hunters/flutter_shaders/tree/main/source/images/Hex_GLSL_colour.png)