1 files changed, 48 insertions, 0 deletions
diff --git a/src/GLSLShaderTest/polkadot3d.frag b/src/GLSLShaderTest/polkadot3d.frag
new file mode 100644
index 0000000..b341454
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+++ b/src/GLSLShaderTest/polkadot3d.frag
@@ -0,0 +1,48 @@
+//
+// Fragment shader for 3 dimensional polka dot shader.
+//
+// Author:  Joshua Doss
+//   
+// Copyright (C) 2002-2004  3Dlabs Inc. Ltd.
+//
+// See 3Dlabs-License.txt for license information
+//
+varying float LightIntensity;
+varying vec3 MCPosition;
+
+//Create uniform variables so dots can be spaced and scaled by user
+//uniform vec3 Spacing;
+//uniform float DotSize;
+const vec3 Spacing = vec3 (0.314, 0.36, 0.261);
+const float DotSize = 0.123;
+
+//Create colors as uniform variables so they can be easily changed
+//uniform vec3 ModelColor, PolkaDotColor;
+const vec3 ModelColor = vec3 (0.75, 0.2, 0.1);
+const vec3 PolkaDotColor = vec3 (1, 1, 1);
+
+void main(void)
+{
+   float insidesphere, sphereradius, scaledpointlength;
+   vec3 scaledpoint, finalcolor;
+
+   // Scale the coordinate system
+   // The following line of code is not yet implemented in current drivers:
+   // mcpos = mod(Spacing, MCposition);
+   // We will use a workaround found below for now
+   scaledpoint       = MCPosition - (Spacing * floor(MCPosition/Spacing));
+
+   // Bring the scaledpoint vector into the center of the scaled coordinate system
+   scaledpoint       = scaledpoint - Spacing/2.0;
+
+   // Find the length of the scaledpoint vector and compare it to the dotsize
+   scaledpointlength = length(scaledpoint);
+   insidesphere      = step(scaledpointlength,DotSize);
+   
+   // Determine final output color before lighting
+   finalcolor        = vec3(mix(ModelColor, PolkaDotColor, insidesphere));
+
+   // Output final color and factor in lighting
+   gl_FragColor      = clamp((vec4( finalcolor, 1.0 ) * LightIntensity), vec4(0.0), vec4(1.0));
+}
+