Draw a radial. This needs some cleanup, and some MVP matrix tweaking.

scwx-qt/gl/radar.frag

@@ -0,0 +1,13 @@
+#version 330 core
+
+// Lower the default precision to medium
+precision mediump float;
+
+uniform sampler2D uTexture;
+
+in vec2 texCoord;
+
+void main()
+{
+   gl_FragColor = vec4(1.0f, 0.0f, 0.0f, 1.0f);
+}

scwx-qt/gl/radar.vert

@@ -0,0 +1,17 @@
+#version 330 core
+
+layout (location = 0) in vec2 aPosition;
+layout (location = 1) in vec2 aTexCoord;
+
+uniform mat4 uMVPMatrix;
+
+out vec2 texCoord;
+
+void main()
+{
+   // Pass the texture coordinate to the fragment shader
+   texCoord = aTexCoord;
+
+   // Transform the position to screen coordinates
+   gl_Position = uMVPMatrix * vec4(aPosition, 0.0f, 1.0f);
+}