glClearColor — specify clear values for the color buffers
                void glClearColor(
               | 
              GLfloat red, | 
| GLfloat green, | |
| GLfloat blue, | |
GLfloat alpha); | 
            
red, 
              green, 
              blue, 
              
                
                  alpha
                
              
            Specify the red, green, blue, and alpha values used when the color buffers are cleared. The initial values are all 0.
            glClearColor specifies the red,
            green,
            blue,
            and alpha values used by glClear to clear fixed- and
                        floating-point color buffers.
            Unsigned normalized fixed point RGBA color buffers are cleared to color values derived by clamping each component of
                        the clear color to the range
            ,
                        then converting the (possibly sRGB converted and/or dithered) color to fixed-point.
        
            glGet with argument GL_COLOR_CLEAR_VALUE
        
| OpenGL ES API Version | ||||
|---|---|---|---|---|
| Function Name | 2.0 | 3.0 | 3.1 | 3.2 | 
| glClearColor | ✔ | ✔ | ✔ | ✔ | 
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