Fix depth test not working for glyphId framebuffer

We need a depth buffer texture as well

modules/exoplanetsexperttool/rendering/renderableexoplanetglyphcloud.cpp

@@ -545,6 +545,25 @@ void RenderableExoplanetGlyphCloud::createGlyphIdTexture(const glm::uvec3 dimens
         *_glyphIdTexture,
         0
     );
+
+    // And a depth buffer of the same dimension
+    _depthTexture = std::make_unique<ghoul::opengl::Texture>(
+        dimensions,
+        GL_TEXTURE_2D,
+        ghoul::opengl::Texture::Format::DepthComponent,
+        GL_DEPTH_COMPONENT32F,
+        GL_FLOAT
+    );
+    _depthTexture->setFilter(ghoul::opengl::Texture::FilterMode::Linear);
+    _depthTexture->uploadTexture();
+    _depthTexture->bind();
+
+    glFramebufferTexture(
+        GL_FRAMEBUFFER,
+        GL_DEPTH_ATTACHMENT,
+        *_depthTexture,
+        0
+    );
 }
 
 void RenderableExoplanetGlyphCloud::mapVertexAttributes() {

modules/exoplanetsexperttool/rendering/renderableexoplanetglyphcloud.h

@@ -112,6 +112,7 @@ private:
 
     // Point id from screenspace position
     std::unique_ptr<ghoul::opengl::Texture> _glyphIdTexture;
+    std::unique_ptr<ghoul::opengl::Texture> _depthTexture;
     GLuint _glyphIdFramebuffer = 0;
 
     glm::ivec2 _lastViewPortSize;