Further, the shader code must use multisampling sampler types and texelFetch() instead
    of texture().

For example, if you have code like

\code
#version 150

uniform sampler2D colorTexture;
in vec2 texCoord;
out vec4 fragColor;

void main()
{
    fragColor = texture(colorTexture, texCoord);
}
\endcode

you can rewrite it as

\code
#version 150

uniform sampler2DMS colorTexture;
in vec2 texCoord;
out vec4 fragColor;

void main()
{
    ivec2 tc = ivec2(floor(textureSize(colorTexture) * texCoord));
    vec4 c = texelFetch(colorTexture, tc, 0) +
                texelFetch(colorTexture, tc, 1) +
                texelFetch(colorTexture, tc, 2) +
                texelFetch(colorTexture, tc, 3);
    fragColor = c / 4.0;
}
\endcode
