REXM: Updated some examples inconsistencies

examples/others/resources/shaders/glsl120/point_particle.fs

@@ -0,0 +1,14 @@
+#version 120
+
+// Input uniform values
+uniform vec4 color;
+
+// NOTE: Add your custom variables here
+
+void main()
+{
+    // Each point is drawn as a screen space square of gl_PointSize size. gl_PointCoord contains where we are inside of
+    // it. (0, 0) is the top left, (1, 1) the bottom right corner
+    // Draw each point as a colored circle with alpha 1.0 in the center and 0.0 at the outer edges
+    gl_FragColor = vec4(color.rgb, color.a*(1.0 - length(gl_PointCoord.xy - vec2(0.5))*2.0));
+}