load shaders from files.

vis/shaders/stereo.vs.glsl

@@ -0,0 +1,15 @@
+#version 430
+
+layout(location=0) uniform mat4 proj;
+layout(location=1) uniform mat4 view;
+
+layout(location=0) in vec4 pos;
+
+out vec4 vpos;
+
+void main() {
+    int i = gl_VertexID;
+    vpos = view * pos;
+     gl_Position = proj * vec4(vpos.xyz / (1 - vpos.w), 1);
+    gl_PointSize = 5;
+}