Difference between revisions of "Radish Trial 6 Advanced Scenes"
(part of trial 6 ported to wiki format)
Revision as of 15:37, 1 August 2020
The trial of the radishes is meant as a guided, self-learning tutorial without step-by-step instructions. Instead it focuses on exploratory learning by actively using the tools to solve increasingly challenging tasks.
>> Trail 6 focuses on creating more advanced scenes <<.
This article provides some background information and various tips required or helpful to accomplish these objectives.
See forum post for more information about the trials.
Some background Information
In the previous trial the focus was set on interactive dialogue scenes and the dialogue flow. Now it’s time to concentrate on the presentation, that is: fine-tune animations, mimics, voicelines and camera framing. This will not only make dialogue scenes more interesting but also allow to create more engaging cinematic cutscenes which present questprogress without player interaction.
Adjusting animations and camera framing is only one part of the story. A cinematic scene should also have some visual structure to support the narrative. This a very broad topic and way beyond the scope of this article. As a start read at least this short introduction which touches some aspects as this article only focus on the technical side.
Rule of Thirds
One simple cinematography technique which is also mentioned in the above introduction is the “Rule of Thirds”. It’s a rule of thumb on how to frame the shot to make the composition look more interesting: the camera frame should be dived by two equally spaced horizontal and vertical lines and important elements of the scene should be placed along those lines or their intersections.
Storyboard UI supports this by providing a Rule-of-Thirds overlay in the camera mode:
The overlay can be toggled on and off with a hotkey.
In addition to a visually pleasing frame composition and varying between appropriate static shot types, scenes can also benefit from carefully defined camera movements. In the Witcher 3 scene system this works by defining two or more key frames (meaning a specific camera position and its direction) and letting the scene system smoothly interpolate the camera position and direction (and other parameters) automatically between the key frames.
Storyboard UI does not provide any direct support or preview for camera setting interpolation. Instead it is required to define separate shots with static cameras in SBUI and afterwards connect these cameras in the scene yml definition by setting up the first camera as a start cam and the second one as the end cam. In the encoder this is called camera blends and an example definition may look like this:
In this case the camera blend starts in the element
shot_1 and ends in the element
shot_3 because it spans multiple voicelines which have to be separate elements. But that is not necessary: it’s possible to define multiple (but not overlapping!) camera blends in one element, e.g. a long pause element without any voicelines. However camera blends cannot span dialog sections boundaries and cannot be defined in choice sections.
Depending on the defined duration (that is the time between the key frames) the interpolation between the camera parameters will be slower or faster. Most of the time only a subtle, very slow movement will improve the scene while fast changes will most likely draw too much attention from viewers and distract from the actual content.
Be aware that smoothly also means that interpolation between more than two key frames (which can be inserted between start and end) will be a curve that may overshot the key frame significantly if not carefully defined. Some experimentation will be necessary.
One simple encode-able example can be found in the docs.scenes/test.examples directory (test_storyboard_cam.blend.yml) which also explains the parameters. The “bigbunny.example” in docs.scenes is an example of a camera flyby with multiple keyframes.
Depth of Field and Focus
An advanced cinematography technique is to adjust the depth of field (DOF). It’s the area in front of the camera that appears sharp and can be used to direct the attention of viewers to certain elements and to blur out unimportant ones, e.g. crowds of npcs surrounding the main actor(s) of the scene.
Here is are three example shots of the same scene with different DOF settings to visualize the effect (click on the image to see the video with rapid switches between the dof settings):
The camera definitions logged from Storyboard UI contain a default DOF setting:
But in most cases it should be adjusted (or at least tuned down) as it makes the encoded scenes “blurry” if the actors are not in the focused sweet spot area.
Both (blur and focus) settings are specified by two distance values (near, far) which (as a simplified analogy) define the range from the camera position that the blur and focus is centered around. So to put some actor(s) (or the interesting scene element) into focus and blur out the near and far parts of the scene the settings should be spaced roughly like this:
[ ... blur near ... [focus near ... actor(s) ... focus far] ... blur far ... ]
It’s possible to change the values individually in SBUI but most of the time it is easier to use the rough (!) automatic DOF centering (see hotkey help). It tries to adjust the settings to “somewhat adequate” values that put the selected actor into the sweet spot of the current shot.
Though the settings can be tweaked individually afterwards, too.
Unfortunately due to technical limitations there is only limited support to preview the effect in SBUI. As a prerequisite for the preview to work at all no active layered environment definitions are allowed (for example no weather environment must be active). Even in this case the preview in SBUI works only partially and only the ‘far’ plane is blurred but not the ‘near’ area. However it is possible to deactivate layered environments with the console command
envui_disable_envs() which is part of the envui package. But make sure the depth of field is not switched off in the games post-processing settings!
As a side note it’s also noteworthy that the DOF settings like all camera parameters will be interpolated in camera blends which can be used to create interesting visual effects.