GDD (Microbe): Game Screens

As the flowchart above shows, on running the game the player will be shown the opening cutscene (skippable with a key press – likely escape, enter and the space bar) while the main title screen loads in the background. Every other game state can be accessed via the title screen menu, though some (like the environment and editor) rely on choices in either the game setup screen or load game screen.

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Title Screen

The title screen (or main menu) is the hub for all other game states. There are links to it from the environment, editor, credits, tools main page, extras main page, game setup screen, load game screen and an automatic link from the opening cutscene.

Only one background will be used for the title screen – a star-filled spacescape with distant nebulae and a single nearby star. In the top centre of the background will be a planet hanging in space, over which the Thrive logo is superimposed. Ideally, there should be slight animations in background elements, such as comets shooting across the sky, varying brightness of nearby stars and the planet gradually spinning in place.

The soundtrack for this screen consists only of the Main Theme (shorter version), looping continuously. Other than GUI sounds, there are no sound effects.

Below the planet and logo is a vertically positioned button list. The buttons follow the GUI design scheme and all have the same shape and dimensions. All link to their respective game screen, ‘New Game’ taking the player to the game setup screen, ‘Load Game’ opening the game loading interface and ‘Exit’ quitting the game (with a confirmation dialog). The options (in vertically descending visual order) are:

  • New Game – Switches the title screen GUI with the game setup interface to start a new game.
  • Load Game – Switches the title screen GUI with the game loading interface to load a previously saved game.
  • Options – Switches the title screen GUI with the options panel for editing game properties.
  • Tools – Switches the title screen GUI with the tools page.
  • Extras – Takes the player to the extras page.
  • Credits – Fades out the title screen and plays the credits cutscene.
  • Exit – Closes the game.

In the lower right hand corner of the screen is the version label as a simple text box overlay.

Setup Interfaces

What will be shown on-screen before the player enters the game.

Initial Setup Interface

When setting up any new game from the title screen, the player uses the game customization interface. As of yet it is undecided whether this consists of an entirely new scene or simply a new GUI on the same background. Either way, the music will play continuously between them, and sound effects are still limited to those associated with the GUI.

The GUI layout consists of one main window containing all game customization options. A ‘Back’ button, returning the player to the title screen, is located in the lower left corner of the screen, while a ‘Play’ button in the right lower corner initiates a new game with the chosen game parameters. The exact design of the main window is entirely up for debate, but it should include the following options:

(Note that some options will carry over to later stages for existing saved games, but many are missing as they only apply to later stages. When new options are made available in a more recent release, the player should somehow be prompted to choose these values if loading an existing saved game).

  • Homeworld Type – A dropdown selection of planet types ('Planet', 'Satellite', 'Random'). This won't have a major effect on the Microbe Stage, but will determine planetary features for later stages.
  • Satellite Number – A slider from zero to ten determining the number of moons the player's homeworld has. The player can instead choose to randomize this number via a checkbox below the slider. Again, this option has little bearing on the Microbe Stage.
  • Terrestrial to Aquatic Ratio – Allows the player to choose how much of their planet is covered in water, though only in vague terms ('Fully terrestrial', 'Mostly terrestrial', 'Balanced', etc.). There is some randomisation to the exact level (so a 'Fully aquatic' planet may have the odd tiny island), though it will roughly fit within the player's choice. Doesn't affect the Microbe Stage.
  • AI Difficulty – Broad descriptions of AI difficulty levels ('Hard', 'Medium', 'Easy'). Only applies to the AI's decision making ability, not its evolution rate or other variables.
  • Tutorial – A checkbox determining whether the player is given a tutorial. Tooltips are included irrespective of this setting.
  • NPC Evolution Rate – A slider or spin button which modifies the time taken for each generation of an NPC microbe species relative to the rate of CPA evaluations. Higher values correspond to higher difficulties (as Auto-Evo can more quickly adapt to changes in the environment with a shorter generation time), so balances should be found to accommodate for easy, medium and hard difficulties. These options are presets available to the player. The range is bound between a lowest possible value and highest, also found by testing for balance.
  • Natural Disaster Frequency – Multiple in-game disasters accompanied by sliders determining their frequency. Even at their highest state, disasters of all types should be relatively infrequent. If an option is disabled, the player will never experience the corresponding disaster during that save. Some disasters (meteor strikes, gamma ray bursts) may end the game without warning, so the player is given a popup saying their game may end at any point if they increase these beyond zero.
  • Compound Concentration – A drop-down box with several options determining overall compound abundance within the environment. Options include ‘Sparse’, ‘Abundant’, and several intermediary options.
  • Start Biome– The player chooses one of several microbial start locations (tide pool, stromatolite, hydrothermal vent, etc.) by clicking on one circular icon from a set with various locations represented pictorially. Changes in the environment arising from this choice are currently uncertain, but visual styles (such as background and favorable microbe coloration) will definitely vary. It may be that this option determines compound concentration, although this would lead to location being tied to difficulty.
  • Mutation Budget – A slider or text field to change the player’s available Mutation Points each generation. The default (medium difficulty) is 100, and all organelle costs should be decided based on this number to allow sensible changes in each generation. Higher mutation budgets correspond to lower difficulties and vice versa.
  • Endocytosis Chance – Varies the chance of successful endocytosis of a bacterium-based organelle. Giving endocytosis a high probability may make the game unplayable for several reasons, so it's yet to be decided whether the player can choose to do so.
  • LAWK – A checkbox toggling Life As We Know It in-game. Un-checking this option will enable fictional organelles such as thermoplasts, while leaving it checked will restrict gameplay to only scientifically accurate concepts.

Though all options can be customized individually, there are several presets for the player to choose from via a dropdown menu at the top of the screen. Some are variations in difficulty, whereas others simply offer a different game experience. Picking one sets all other options to a set of values previously chosen by the developers. Choosing a preset applies its settings but the player can still make edits. These will be finalised once the other options are in place, but here are some proposals:

  • Classic (Normal or random settings for everything, LAWK on, etc.)
  • Terracentric (Start on a balanced land to water planet with one satellite, normal settings, LAWK on, etc.)
  • Beginner (Balanced homeworld options, low AI difficulty and NPC evolution rate, tutorial, no disasters, high compound concentration and mutation budget, etc.)
  • Hardcore (All the hardest options, high disaster rates, slow evolution rates, fully random homeworld, etc.)
  • Random (Randomizes every option)

Loading Interface

Like the game customization interface, loading the game may not involve a change of scene, merely a modification of the GUI. The Main Theme continues to play, and only GUI sound effects are used.

Above the ‘Back’ and ‘Play’ buttons in each lower corner (the latter grayed out until the player makes a selection) is a list of saved game states in a scrollable window. The player may click a saved item in the list, before clicking ‘Play’ to return to that save. While this is the bare minimum required for the loading interface, it might be useful to include basic information about a selected save taken from its setup parameters. This would constitute a set of icons (like that representing the start location) or text fields.


The microbial environment is the player’s main view for the majority of the game. It can only be accessed through the game setup screen from the main menu, or through completing a generational mutation in the editor.

GUI is minimal to reduce view obstruction, but several areas of the screen are covered by translucent panels containing information. The arrangement of panels is yet to be decided upon, but those required are:

  • Species Name – The name the player gave their species in the editor. Before their first editor session, this will take a default value.
  • Editor - Grayed out until the player has collected enough compounds to fill their reproduction meters. Switches game states to the editor. Icon is a stylized depiction of a cell undergoing mitosis.
  • Compounds List – All the player's current compounds. Representing this in the most intuitive manner will be a challenge. This panel can be expanded or shrunk with a hotkey. Compounds are identified by their respective icons.
  • ATP Meter – A "progress bar" showing the player's current ATP level. Effectively an energy meter.
  • Locked-Up Compounds – Bars representing the player's progress towards the necessary compounds for reproduction to occur. Healing organelles will extract organelles from these bins, while the total required is determined by the player cell's construction.
  • Save – A stylized floppy disk icon which, when clicked, pauses the game and opens a save dialogue. The player can either enter a name, use the placeholder save name (the structure which is undecided) or quicksave. The former requires the player to click a ‘Save’ confirmation to return, while the latter replaces the last quicksave and returns the player to the environment immediately.
  • Load – When the player clicks the load button (the icon for which could be a downward-facing arrow), the game is paused and the player is asked whether they’d like to save the game in progress first, bringing up the save dialogue if true. Afterwards, another center-aligned panel appears. Saved games are listed in reverse chronological order and can be scrolled through. Selecting one activates a confirmation button which loads the selected game state.
  • Help – Similarly, clicking help pauses the game and brings up a central panel containing either descriptions of game mechanics or pictorial representations of player actions. Options to replay the tutorial are also shown. Choosing to replay the tutorial saves the game in progress and sends the player back to the start. Unlike the initial tutorial, the player does not continue when finished, instead returning to the saved game automatically.
  • Options – A gear icon which pauses the game and brings up a simplified version of the main game options. Only those relevant to a game in progress are included (resolution is omitted, for instance) and can be modified before the player clicks a ‘Close’ button to return to the environment.
  • Statistics – A button featuring a graph icon which pauses the game and shows a statistics overlay. Metrics about the player’s microbe and population dynamics are taken directly from the background simulation, such as the biomass of each species and a list of processes within the player’s cell. There is a ‘Close’ option to return to gameplay.
  • Pause Menu – When the player presses escape, the game is paused and a simple menu appears in the center of the screen, with options of ‘Resume’, ‘Exit to Main Menu’ and ‘Exit to Desktop’. The current game options (such as chosen location and AI difficulty) are also displayed. Other buttons from this list may be integrated into it.
  • Exit to Main Menu – Shows a confirmation dialog, before leaving the game.
  • Exit to Desktop – Shows a confirmation dialog, before leaving the game and exiting straight to desktop.
  • Suicide Button – When a microbe with a cell wall has no energy reserves left, it can survive until all its organelles lose all their health. It is possible to return from this situation, but not particularly likely and most players won’t want to go through with it. This means there must be a suicide button which appears somewhere on-screen when a cell’s ATP level reaches zero but it continues to survive. Alternatively, it could always be on screen, giving the player an option to kill their cell at any time if things aren’t going well. Includes a confirmation dialog to prevent accidents.
  • Fossilization Panel – If a player encounters an NPC cell they wish to save, they can right click on it to bring up the fossilization panel. This hovers next to the chosen cell and travels with it, disappearing if the cell moves beyond the edge of the screen. It consists of an ammonite icon next to a text box and confirmation button. The player can enter a name and save the species by clicking the confirmation button, the panel disappearing. From then on, any cells of that species will be labelled in the environment with hovering text. Fossilization allows file sharing between players or the use of a species in the editor (provided they have the necessary Mutation Points if using the gameplay editor).
  • Organelle priorities – If the player pauses the game using the space bar, each organelle in their microbe is given a panel showing player-chosen priorities for an organelle’s use of compounds. At the moment it’s unknown how this will look, though it will need to quantify the relative priorities of each compound in each organelle. It must also have options for each organelle to toggle it on or off, and regenerate it using ATP if it stops functioning.

The compounds panel is displayed in the lower right corner of the screen, at first as a small labelled button. It exhibits the same expansion properties as the lower left menu (i.e. hovering opens temporarily, clicking or hotkey toggles permanently until next toggle). When open, the panel expands to fill most of the lower right screen, displaying the player’s compound stores relative to total storage space as radar charts. Each compound is identified by its icon, with tool-tip labels appearing when hovered over. The radar charts auto-update to reflect the game in real-time.

Behind the player and NPC cells is a tiled background image reflecting the chosen starting location (e.g. backgrounds for a hydrothermal vent may have more red and brown coloration, while a tide pool would be largely green, yellow and blue). The color of the background in each location determines the general appearance of cells which spawn there (though this has little gameplay value as camouflage isn’t relevant to cellular gameplay, it does create a unique aesthetic for each environment). As the player moves, the view of the screen moves with them to keep them focused in the center, though screen rotation is handled manually through right-clicking and dragging. The player may also zoom in and out smoothly within maximum and minimum bounds.

The foreground is populated with the player’s cell, NPC cells, floating items, compound clouds, heat and light spots, and water currents. Water currents are represented by slight shading over the background and are tied to the grid-based compound display, hence compound clouds billow and dilute in the direction of water flow. All other items travel in the direction of the currents (some faster than others due to variances in inertia), except cells with flagella in motion.

There are two continuous sound layers in the environment – music and ambiance. Ambiance is a quiet, looped soundscape which imitates an underwater atmosphere with sporadic, source-less water splashes and bubbles to give the impression of sounds outside the player’s immediate vicinity. Microbe Gameplay Themes are played over the top, largely blocking out the ambience for all but the quietest sections. Each time a track ends or the player enters from another scene, a track from the available Gameplay Themes is chosen and starts. This is done somewhat randomly, weighted against playing the same track twice in succession. On exiting the environment in any way, the music and ambiance fade out. Returning from the editor is the only occasion when a track picks up from where it left off.

Sound effects (other than those for the GUI or player actions) are determined by proximity to the player. Those closer are louder, with volume changes handled by the engine by comparing distances. Most are related to cell movement. All point sound effects are muted while the game is paused, while music and ambiance continue playing.


While the player spends most of their time in the environment, their success in gameplay is determined by how thoughtful they are in the organism editor, where the player can change their species’ physical and behavioral characteristics.

The main microbe editor is accessed only from the environment, but a free edit version (with no Mutation Point cap but no ability to use a microbe in gameplay) is linked from the tools page. In the free edit editor, buttons returning the player to the environment are grayed out, but all other functions are available.

As in the environment, the player’s microbe is held at the center of the screen, this time unmoving, except for slight twitches in flagella, cilia and the membrane. An arrow points upwards to indicate the front of the cell, and the player can right click and drag to rotate the scene around the central microbe. The background is the same as the environment, with only water currents in the foreground (though they do not affect the player cell in this view). The player can also zoom as usual.

A panel with the species name (with the same dimensions as the corresponding panel in the environment) is featured in the top left corner. Clicking on the name allows it to be edited. Below is a button with a microbe and plus sign indicating ‘New Microbe’. This is only available in free edit mode as the Mutation Point costs would be too great for a completely new microbe to be created in a single normal generation.

The same expandable menu covers the lower left of the screen, though some buttons now have different functions:

  • Save – Fairly similar to the environment version, though this time it handles organism saving and doesn’t allow quicksaving.
  • Load – Same functionality as in the environment but for saved microbes instead of game states. However, most options will be un-selectable. Only those which can be created from the current microbe with the Mutation Point budget or less (that is, those fairly similar to the current microbe) can be loaded. This is the only time creations from free edit mode can be used in gameplay.
  • Options – Same as in the environment.
  • Help – Same as in the environment.
  • Statistics – Now displays metrics about the current cell, such as volume, surface area and maximum speed, along with available processes and the organelle efficiency for each.

In the lower right hand corner of the screen is the player’s mutation budget, which is the same for all entries to the editor at the same difficulty level (e.g. 100 at medium difficulty). A stylized DNA icon sits beside the number. Next to the mutation budget panel is the ‘Finish’ button, returning the player to the environment with the changes they’ve made. The first time the player enters the editor, ‘Finish’ may only be clicked after saving the microbe. Subsequent editor exits will autosave the current cell, replacing the previously used saved cell file. The top right features the same main menu and exit buttons as in the environment, with the same confirmation dialogues. The pause menu can still be accessed as in the environment.

Below the cell are the ‘Undo’ and ‘Redo’ buttons, and the symmetry panel. The symmetry panel initially displays a single vertical line, referring to two times symmetry in placing organelles and cytoplasm. Clicking it once creates four times symmetry with vertical and horizontal axes, clicking it again creates six times symmetry with three intersecting lines positioned at 120 degree intervals, clicking again removes all lines to remove symmetry, and clicking it a final time returns it to the initial state. Symmetry is grayed out for everything but structure editing. Undo and redo are grayed out if no changes have been made or undo has not been clicked respectively.

The only sound effects are those related to the GUI and occasional microbe movement (such as a few splashes when adding a flagellum). Ambiance and music play in the same manner as in the environment, using Microbe Editor Themes rather than Microbe Gameplay Themes.

Editing Panel

Most of the player’s actions in the editor will involve the editing panel, which takes up the entire right side of the screen between the main menu button and mutation budget panel. It’s used for all editing of a microbe and its behavior, and is divided into several sections (initially collapsed headings which expand on click, collapsing any other open sections):

  • Structure – When activated, a hexagonal grid appears behind the cell and its membrane disappears. Organelle models are replaced by icons in hexagons, and the cytoplasm becomes a patchwork of white squares. A ring of highlighted hexes appears, tracing out a large hexagon centered on the nucleus. This is the size limit for the cell – as a player progresses further through the game, the maximum size increases, so the hexagon gradually expands over several editor sessions. The collapsed ‘Structure’ heading expands to show a scrollable list of organelles, each represented by a slightly animated organelle model. Clicking an organelle already placed in the cell replaces this list with the organelle’s stats and upgrade options.
  • Appearance – When activated, a 3D membrane is traced around the cell based on its hexagon arrangement, and organelles begin floating through it as they would in-game. The ‘Appearance’ heading expands to show coloration options, as well as a list of external organelle shaders which change the covering on the cell and grant different abilities. Clicking the shader replaces the coloration options and organelle list with upgrade options for the covering(s).
  • Behavior – When activated, the cell and background are replaced by a behavior editor based on a hex grid. Some GUI panels slide out of the screen as they aren’t needed, but return on choosing a different option in the editing panel. Inputs and outputs are listed under the ‘Behavior’ heading in the editing panel, along with an agent synthesizer.
  • Test – When activated, all GUI panels except the species name panel, main menu button and exit game button retract into the sides of the screen. Two new panels appear in the lower middle of the screen. One returns to the editor, while the second allows the player to choose new cells to populate the environment (loading them from the same loading system as in the regular editor but with no Mutation Point restraints). The player can now move the cell as if it were in the environment, testing out its effectiveness on enemies, or testing the AI of the player’s own species.


In the options screen, the player can make changes to game properties. Like the game setup screens, it involves no change in background or sound from the title screen, only a differing GUI layout.

The GUI could either be a single panel or broken up into multiple panels for different sections. There is a ‘Save’ button somewhere below all options for saving all changes in options and returning to the main menu, and a ‘Back’ button to return without making any changes. Editable options are:

  • Resolution – Changes the screen resolution, requiring a game restart to come into effect.
  • Volume – Separate sliders for changing the volume of music, ambiance and sound effects.
  • Difficulty – Sets the default difficulty level for new game setups.
  • Experience Level – Sets the default experience level for new game setups.
  • Controls – Key rebinding options for keyboards and mouse. Each action (move, release agent, etc.) is paired with a control which can be edited by clicking in the box and pressing the key the player wishes to use. Editable controls are limited to binary commands, so mouse movement cannot be rebound.
  • Autosave Frequency – Determines the frequency of autosaves while playing. Each autosave overwrites the last one in a particular game.

Extras and Tools

These two sections aren’t essential for the overall game experience, but do include more gameplay options and some bonus material.


The extras page is linked from the main menu. During the transition, the music and screen fade out then back in. The new music is a solo piano arrangement of the Main Theme, creating a calmer feel with more altered chords for a jazz-like style, while the background is a darkened image of the Disturbance.

From the extras page, the player can access concept art and the musical score through separate links (there is also a ‘Back’ button as always to return to the main menu). Concept art is presented as a tiled gallery, where clicking an image makes it expand to fill the whole screen (the player can press escape or click again to return). The musical score is a vertically ordered track list with each track playable by clicking a play icon next to it, the Main Theme quickly fading out to make room.


Unlike the extras page, the tools page is not an entirely new scene. Background and music remain constant from the title screen – only the GUI changes. Like the options screen, the vertical button list is replaced with either a single panel or multiple panel sections, and a ‘Back’ button.

Currently there are only two planned tools: free edit mode and a debugger. Free edit mode opens the editor scene with no mutation budget, allowing the player to experiment outside the game. Free edit microbes can be loaded into the editor during actual gameplay, but only if the changes needed to turn the current cell into the new one are below the Mutation Point threshold set by the difficulty level.

The debugger can be activated from the tools page, opening a panel overlay where code can be typed during any scene. It can be dragged around or re-sized, and remains on screen throughout any scene until the player returns to the tools page and deactivates it.

Loading Screens

Ideally, loading screens should only appear when starting the game after the opening cutscene or entering the environment/editor from the main menu. They have no GUI or sound effects, instead featuring a static background with music playing.

The background is randomly chosen each time from microbe stage concept art, with ‘Loading…’ added as a text box in the lower right corner. There should be a progress bar beneath the text with a simple form of animation. For environment loading screens, there could be an image of the player’s microbe displayed somewhere on-screen so they can remember which save they’re entering if it’s been a while.

Music is randomly chosen each time from the Loading Screen Themes. On the very rare occasion that the loading screen lasts longer than the track, a new one starts up, weighted against the same track playing twice in succession. This shouldn’t happen though, so it’s just a precaution.

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