Add icons for (x, y) placement on the map

scwx-qt/gl/texture2d_array.vert

@@ -0,0 +1,26 @@
+#version 330 core
+
+#define DEG2RAD 0.0174532925199432957692369055556f
+
+layout (location = 0) in vec2  aVertex;
+layout (location = 1) in vec2  aXYOffset;
+layout (location = 2) in vec3  aTexCoord;
+layout (location = 3) in vec4  aModulate;
+layout (location = 4) in float aAngleDeg;
+
+uniform mat4 uMVPMatrix;
+
+smooth out vec3 texCoord;
+smooth out vec4 color;
+
+void main()
+{
+   // Rotate clockwise
+   float angle  = aAngleDeg * DEG2RAD;
+   mat2  rotate = mat2(cos(angle), -sin(angle),
+                       sin(angle), cos(angle));
+
+   gl_Position = uMVPMatrix * vec4(aVertex + rotate * aXYOffset, 0.0f, 1.0f);
+   texCoord    = aTexCoord;
+   color       = aModulate;
+}