Graphics configuration

Most of the graphics settings can be adjusted using the Preferences dialog.

Resolution and mode

You can find the Resolution and mode configuration under the Graphics tab.

  • Display mode – select between fullscreen mode and windowed mode. In the case of full screen, you can choose the resolution from a list of supported resolutions in a drop down menu. If you choose windowed mode, you can enter the resolution you want. You can also choose whether the window should be resizable or not. In order to switch from full screen mode to windowed mode during the execution, use the key F11.

  • V-sync – enable v-sync to limit the frame rate to the refresh rate of your monitor. In some cases this may help reducing tearing.

  • Maximum frame rate – it is possible to set a maximum frame rate by ticking this checkbox and entering a positive integer value. The frame rate will be capped to that value.

Graphics settings

Graphics quality

This setting governs the size of the textures, the complexity of the models and also the quality of some graphical effects like the star glow or the lens flare. Here are the differences:

  • Low – very low resolution textures, mostly 1K (1024x512), and fewer sample counts for the visual effects than in higher quality settings. Low-fidelity Milky Way model.

  • Normal – moderately low resolution textures (2K when available). The graphical effects use a reasonable amount of quality for nice visuals without compromising the performance too much. Medium-fidelity Milky Way model.

  • High – high-resolution 4K (3840x2160) textures. Graphical effects use a large number of samples. High-fidelity Milky Way model. This may be taxing even on good graphics cards.

  • Ultra – very high resolution textures (8K, 16K, etc.). Ultra-high-fidelity Milky Way model.


In the Graphics tab you can also find the antialiasing configuration. Applying antialiasing removes the jagged edges of the scene and makes it look better. However, it does not come free of cost, and usually has a penalty on the frames per second (FPS). There are four main options, described below.

Find more information on antialiasing in the Antialiasing section.

No Antialiasing

If you choose this no antialiasing will be applied, and therefore you will probably see jagged edges around models. This has no penalty on either the CPU or the GPU. If want you enable antialiasing with override application settings in your graphics card driver configuration program, you can leave the application antialiasing setting to off.

FXAA – Fast Approximate Antialiasing

This is a post-processing antialiasing filter which is very fast and produces very good results. The performance hit depends on how fast your graphics card is, but it is generally low. Since it is a post-processing effect, this will work also when you take screenshots or output the frames. As of Gaia Sky 2.2.5, FXAA is activated by default. Here is more info on FXAA.

NFAA – Normal Field Antialiasing

This is yet another post-processing antialiasing technique. It is based on generating a normal map to detect the edges for later smoothing. It may look better on some devices and the penalty in FPS is small. It will also work for the screenshots and frame outputs.

Since 3.2.0

Point cloud style

The point cloud rendering style. This affects the rendering of all particle datasets (Oort cloud, SDSS, etc.), stars (including Hipparcos and all Gaia-based catalogs, as well as variable stars) and asteroids.

  • Quality billboards – in this mode, the data points are rendered as billboards (quads composed of two triangles each which always face the camera) using instancing to save VRAM. This is generally the faster option with modern GPUs. This mode produces geometrically correct stars and particles, which means that they have consistent scene orientations in cubemap mode, eliminating the seams completely. Use this when using the panorama or planetarium modes.

  • Legacy (point primitives) – This is the mode used in Gaia Sky before 3.1.7. It uses point GL primitives (GL_POINTS) to render point clouds. The points are rasterized in image space, so they are not consistently projected across the whole field of view. Otherwise, this mode is fine for the regular use of Gaia Sky, and tends to perform better on very old hardware.

Line style

Select the line rendering backend.

  • Quality lines – use geometry shaders to generate polyline quad-strips, resulting in much better-looking and more consistent lines. Trajectories and orbits are also sent to the GPU once, and updated periodically. The use of geometry shaders may have a slight impact on performance with some graphics cards, but it is typically unnoticeable.

  • Legacy (line primitives) – use the line primitives offered by the graphics driver. Since the lines are shaded by the driver implementation, they may differ depending on the graphics card. Trajectories and orbits are sent to the GPU in a buffer only once, the rest of the custom lines are computed on the CPU and sent over each frame.

Star glow over objects

Activate the star glow effect, where the light from close-by stars like the Sun bleeds in front of closer objects like planets, moons or spacecraft.

Lens flare

Set the strength of the lens flare effect. Set to 0 to disable the lens flare. There are currently three different lens flare options, but they need to be chosen directly in the configuration file. See this section for more information.

Bloom effect

This slider controls the amount of bloom (light bleeding from bright to dark areas) to apply to the scene. Bring it all the way down to zero to disable bloom altogether.

Since 3.0.2

Unsharp mask factor

This slider controls the amount of sharpening to apply to the scene with the unsharp mask effect. Increasing the unsharp mask factor makes the visuals sharper but possibly introduces aliasing and visual artifacts. Bring it all the way down to zero to disable the unsharp mask effect.

Since 3.5.0

Chromatic aberration amount

The amount of chromatic aberration to apply to the image. Set to 0 to disable the chromatic aberration effect.

Since 3.5.6

Film grain

The amount of film grain to apply to the image. Set to 0 to disable the film grain effect.

Since 3.2.0

Fade time

Set the time it takes for objects to fade in and out when their visibility is modified, either via the “Object visibility” pane or using the individual visibility toggle. This value is in milliseconds.

Elevation representation

Choose the way elevation (height) is represented in Gaia Sky. This only works when the objects has a height map (texture, cubemap or SVT) attached, and also a height scale. If the object has a normal map, normals are computed from this map. Otherwise, the height texture is used to compute the normals.

  • Regular vertex displacement – displace the object’s vertices along the normal vector to represent height. Note that a heightScale value, indicating the extent of the displacement with an elevation multiplier of 1, is needed for this to work correctly.

  • Terrain tessellation – use geometry subdivision by tessellation for large bodies (planets and moons). For bodies with a rough size greater than about 500 Km, tessellation subdivision is used before displacing the vertices. This may be taxing on integrated or old graphics cards. Disable if frame rate is low. Note that a heightScale value, indicating the extent of the displacement with an elevation multiplier of 1, is needed for this to work correctly.

  • None – do not represent elevation.


Enable or disable shadows, and choose their properties.

  • Shadow map resolution – choose the resolution of the shadow map textures to use.

  • # shadows – how many shadows are active at a time in the scene.

Image levels

Control the image levels

  • Brightness – overall brightness of the image.

  • Contrast – overall contrast of the image.

  • Hue – hue value of the image.

  • Saturation – saturation value of the image.

  • Gamma correction – gamma correction value of the image. This should be calibrated with your monitor.

  • HDR tone mapping type – tone mapping algorithm to use. Choose Automatic to use a real-time adjusting mode based on the overall lightness of the image. All the others are static algorithms.

Since 3.4.0

Virtual textures

This section contains settings related to the sparse virtual texturing system in Gaia Sky.

Cache size

Use this slider to determine the cache size, in tiles. The size of each tile depends on the first virtual texture dataset loaded. Gaia Sky supports only multiple virtual textures in the same scene when all have the same tile size. You can adjust this slider to modify the size of the texture used as cache. The changes apply only the next time you start Gaia Sky.

Since 3.2.0


This section contains experimental graphics options:

  • Post-processing re-projection – use a post-processing shader to re-project the final image, with a varied choice of projection algorithms:

    • Disabled – no re-projection.

    • Default (simple fisheye) – a simple fisheye projection algorithm.

    • Accurate (no full coverage) – a more accurate projection, but has a coverage of 180^\circ, which is not available with the perspective camera.

    • Stereographic (screen fit) - stereographic projection with a screen fit.

    • Stereographic (long edge fit) - stereographic projection with a long axis fit.

    • Stereographic (short edge fit) - stereographic projection with a short axis fit.

    • Stereographic (180 fit) - stereographic projection with a fit to a filed of view of 180^\circ.

    • Lambert (screen fit) - Lambert projection with a screen fit.

    • Lambert (long edge fit) - Lambert projection with a long axis fit.

    • Lambert (short edge fit) - Lambert projection with a short axis fit.

    • Lambert (180 fit) - Lambert projection with a fit to a filed of view of 180^\circ.

    • Orthographic (screen fit) - orthographic projection with a screen fit.

    • Orthographic (long edge fit) - orthographic projection with a long axis fit.

    • Orthographic (short edge fit) - orthographic projection with a short axis fit.

    • Orthographic (180 fit) - orthographic projection with a fit to a filed of view of 180^\circ.

  • Dynamic resolution – in this mode, the resolution of the back-buffer is adapted depending on the frame rate to avoid too drastic slow-downs. The dynamic resolution is adjusted according to some predefined back-buffer scale factors: 1, 0.85 and 0.75. The resolution of the back-buffer is scaled by the next value if the frame rate is below 30, and to the previous level if it is over 60. This should provide smoother frame-rates on older hardware, and in some GPU demanding situations.

  • Back-buffer scale – resolution scale factor to apply to the render frame buffer, effectively rendering the scene at a lower or higher resolution in the background, trading off performance and visual fidelity. This setting is disabled when dynamic resolution is enabled.

    • Set the back-buffer scale to less than one to render the image with a lower resolution, increasing performance and lowering visual fidelity, and upscale it to the window size.

    • Set the back-buffer scale to a value greater than one to render the image with a resolution higher than that of the current window, decreasing performance and increasing visual fidelity, and downscale it to window size.

  • Index of refraction – set the index of refraction of the sphere in orthosphere view mode. The orthosphere is filled up with a material with the given refraction index, with light rays bending and scattering according to their angles of incidence.

  • Screen space reflections – activate SSR (screen space reflections). In this method, a post-process step traces the reflections for each reflective surface in the image. This has an impact on performance but produces nice-looking reflections on metallic surfaces. If this is off, it falls back to cubemap reflections with a default sky box of the milky way. The default location of the sky box is $GS_DATA/tex/skybox/gaiasky.

The welcome screen in Gaia Sky 3.2.0+

A rendering of Gaia with SSR activated