Add dev mode for faster animation

.gitignore

@@ -6,4 +6,5 @@ Manifest.toml
 .vscode/
 test.png
 test/current/
-.commit
+.commit
+.dev

src/Javis.jl

@@ -166,7 +166,8 @@ end
         pathname="javis_GIBBERISH.gif",
         tempdirectory="",
         liveview=false,
-        ffmpeg_loglevel="panic"
+        ffmpeg_loglevel="panic",
+        compute_frames = :all
     )
 
 Renders all previously defined [`Object`](@ref) drawings to the user-defined `Video` as a gif or mp4.
@@ -184,6 +185,8 @@ Renders all previously defined [`Object`](@ref) drawings to the user-defined `Vi
 - `ffmpeg_loglevel::String`:
     - Can be used if there are errors with ffmpeg. Defaults to panic:
     All other options are described here: https://ffmpeg.org/ffmpeg.html
+- `compute_frames`: If specified to `:latest` and `dev_mode` is set for the current [`Video`](@ref), 
+    then it reuses frames which do not have changed since last render. This speeds up the rendering time.
 """
 function render(
     video::Video;
@@ -192,6 +195,7 @@ function render(
     liveview = false,
     tempdirectory = "",
     ffmpeg_loglevel = "panic",
+    compute_frames = :all,
 )
     objects = video.objects
     frames = preprocess_frames!(objects)
@@ -217,10 +221,24 @@ function render(
     end
 
     filecounter = 1
+
+    dev_mode = get(CURRENT_VIDEO[1].defs, :dev_mode, false)
+    if dev_mode
+        last_frames = get(CURRENT_VIDEO[1].defs, :last_frames, frames)
+        tempdirectory = ".dev"
+    end
+
     @showprogress 1 "Rendering frames..." for frame in frames
-        frame_image = convert.(RGB, get_javis_frame(video, objects, frame))
-        if !isempty(tempdirectory)
-            Images.save("$(tempdirectory)/$(lpad(filecounter, 10, "0")).png", frame_image)
+        if compute_frames == :latest && frame in last_frames
+            frame_image = Images.load("$(tempdirectory)/$(lpad(filecounter, 10, "0")).png")
+        else
+            frame_image = convert.(RGB, get_javis_frame(video, objects, frame))
+            if !isempty(tempdirectory)
+                Images.save(
+                    "$(tempdirectory)/$(lpad(filecounter, 10, "0")).png",
+                    frame_image,
+                )
+            end
         end
         if render_mp4
             if frame == first(frames)
@@ -252,6 +270,10 @@ function render(
     else
         @error "Currently, only gif and mp4 creation is supported. Not a $ext."
     end
+
+    if dev_mode
+        CURRENT_VIDEO[1].defs[:last_frames] = frames
+    end
     return pathname
 end
 

src/structs/Object.jl

@@ -73,7 +73,8 @@ function Object(frames, func::Function, start_pos::Union{Object,Point}; kwargs..
     if isempty(CURRENT_VIDEO)
         throw(ErrorException("A `Video` must be defined before an `Object`"))
     end
-    CURRENT_VIDEO[1].defs[:last_frames] = frames
+
+    update_lastframes(frames)
     opts = Dict(kwargs...)
 
     if get(opts, :in_global_layer, false) && frames isa UnitRange
@@ -129,16 +130,19 @@ Here the scaling is applied to the rectangle for the first fifty frames.
    - `action::Vector{<:AbstractAction}` - the actions applied to the objects
 """
 function act!(object::AbstractObject, action::AbstractAction)
+    update_lastframes(action.frames.frames)
     push!(object.actions, copy(action))
 end
 
 function act!(object::AbstractObject, actions::Vector{<:AbstractAction})
     for action in actions
+        update_lastframes(action.frames.frames)
         act!(object, action)
     end
 end
 
 function act!(objects::Vector{<:AbstractObject}, action)
+    update_lastframes(action.frames.frames)
     for object in objects
         act!(object, action)
     end

src/structs/Video.jl

@@ -28,15 +28,18 @@ const CURRENT_VIDEO = Array{Video,1}()
 
 
 """
-    Video(width, height)
+    Video(width, height; dev_mode = false)
+
+Create a video with a certain `width` and `height` in pixel. The argument `dev_mode` 
+specifies whether to reuse frames during development specified by the `compute_frames` 
+paramter in render.
 
-Create a video with a certain `width` and `height` in pixel.
 This also sets `CURRENT_VIDEO`.
 """
-function Video(width, height)
+function Video(width, height; dev_mode = false)
     # some luxor functions need a drawing ;)
     Drawing()
-    video = Video(width, height, AbstractObject[], Int[], Dict{Symbol,Any}())
+    video = Video(width, height, AbstractObject[], Int[], Dict{Symbol,Any}(:dev_mode=>dev_mode))
     if isempty(CURRENT_VIDEO)
         push!(CURRENT_VIDEO, video)
     else
@@ -45,3 +48,25 @@ function Video(width, height)
     empty!(CURRENT_OBJECT)
     return video
 end
+
+"""
+    update_lastframes(frames)
+
+Updates the list of unchanged frames of the current video if `dev_mode` in [`Video`](@ref) is set.
+
+# Warnings
+Shows a warning if argument `frames` cannot be processed to update last frames. Possible 
+when frames passed is a [`RFrames`](@ref), which is fine since these will be newly added.
+"""
+function update_lastframes(frames::Any)
+    try
+        if typeof(frames) == UnitRange{Int64}
+            frames = Vector{Int}(frames)
+        end
+        if get(CURRENT_VIDEO[1].defs, :dev_mode, false)
+            CURRENT_VIDEO[1].defs[:last_frames] =  setdiff(get(CURRENT_VIDEO[1].defs, :last_frames, Vector{Int}()), frames)
+        end
+    catch e
+        @warn "Argument `frames` with type $(typeof(frames)) passed to `update_lastframes` must have integer vector like type hence ignoring update."
+    end
+end