1 -- The theme is what decides what's actually shown on screen, what kind of
2 -- transitions are available (if any), and what kind of inputs there are,
3 -- if any. In general, it drives the entire display logic by creating Movit
4 -- chains, setting their parameters and then deciding which to show when.
6 -- Themes are written in Lua, which reflects a simplified form of the Movit API
7 -- where all the low-level details (such as texture formats) are handled by the
8 -- C++ side and you generally just build chains.
9 io.write("hello from lua\n")
11 local zoom_start = -2.0
16 local live_signal_num = 0
17 local preview_signal_num = 1
19 -- The main live chain.
20 function make_sbs_chain(hq)
21 local chain = EffectChain.new(16, 9)
22 local input0 = chain:add_live_input()
23 input0:connect_signal(0)
24 local input1 = chain:add_live_input()
25 input1:connect_signal(1)
27 local resample_effect = nil
28 local resize_effect = nil
30 resample_effect = chain:add_effect(ResampleEffect.new(), input0)
32 resize_effect = chain:add_effect(ResizeEffect.new(), input0)
35 local padding_effect = chain:add_effect(IntegralPaddingEffect.new())
36 padding_effect:set_vec4("border_color", 0.0, 0.0, 0.0, 1.0)
38 local resample2_effect = nil
39 local resize2_effect = nil
41 resample2_effect = chain:add_effect(ResampleEffect.new(), input1)
43 resize2_effect = chain:add_effect(ResizeEffect.new(), input1)
45 -- Effect *saturation_effect = chain->add_effect(new SaturationEffect())
46 -- CHECK(saturation_effect->set_float("saturation", 0.3f))
47 local wb_effect = chain:add_effect(WhiteBalanceEffect.new())
48 wb_effect:set_float("output_color_temperature", 3500.0)
49 local padding2_effect = chain:add_effect(IntegralPaddingEffect.new())
51 chain:add_effect(OverlayEffect.new(), padding_effect, padding2_effect)
58 resample_effect = resample_effect,
59 resize_effect = resize_effect,
60 padding_effect = padding_effect
64 resample_effect = resample2_effect,
65 resize_effect = resize2_effect,
66 padding_effect = padding2_effect
71 local main_chain_hq = make_sbs_chain(true)
72 local main_chain_lq = make_sbs_chain(false)
74 -- A chain to show a single input on screen (HQ version).
75 local simple_chain_hq = EffectChain.new(16, 9)
76 local simple_chain_hq_input = simple_chain_hq:add_live_input()
77 simple_chain_hq_input:connect_signal(0); -- First input card. Can be changed whenever you want.
78 simple_chain_hq:finalize(true)
80 -- A chain to show a single input on screen (LQ version).
81 local simple_chain_lq = EffectChain.new(16, 9)
82 local simple_chain_lq_input = simple_chain_lq:add_live_input()
83 simple_chain_lq_input:connect_signal(0); -- First input card. Can be changed whenever you want.
84 simple_chain_lq:finalize(false)
86 -- Returns the number of outputs in addition to the live (0) and preview (1).
87 -- Called only once, at the start of the program.
88 function num_channels()
92 -- Called every frame.
93 function get_transitions()
94 return {"Cut", "Fade", "Zoom!"}
97 function transition_clicked(num, t)
100 local temp = live_signal_num
101 live_signal_num = preview_signal_num
102 preview_signal_num = temp
104 if live_signal_num == 2 then
105 -- Just cut to SBS, we need to reset any zooms.
114 -- If live is 2 (SBS) but de-facto single, make it so.
115 if live_signal_num == 2 and t >= zoom_end and zoom_dst == 1.0 then
119 if live_signal_num == preview_signal_num then
124 if (live_signal_num == 0 and preview_signal_num == 1) or
125 (live_signal_num == 1 and preview_signal_num == 0) then
126 -- We can't zoom between these. Just make a cut.
127 io.write("Cutting from " .. live_signal_num .. " to " .. live_signal_num .. "\n")
128 local temp = live_signal_num
129 live_signal_num = preview_signal_num
130 preview_signal_num = temp
134 if live_signal_num == 2 and preview_signal_num == 1 then
135 io.write("NOT SUPPORTED YET\n")
139 if live_signal_num == 2 and preview_signal_num == 0 then
140 -- Zoom in from SBS to single.
145 preview_signal_num = 2
146 elseif live_signal_num == 0 and preview_signal_num == 2 then
147 -- Zoom out from single to SBS.
152 preview_signal_num = 0
158 function channel_clicked(num)
159 preview_signal_num = num
162 -- Called every frame. Get the chain for displaying at input <num>,
163 -- where 0 is live, 1 is preview, 2 is the first channel to display
164 -- in the bottom bar, and so on up to num_channels()+1. t is the
165 -- current time in seconds. width and height are the dimensions of
166 -- the output, although you can ignore them if you don't need them
167 -- (they're useful if you want to e.g. know what to resample by).
169 -- You should return two objects; the chain itself, and then a
170 -- function (taking no parameters) that is run just before rendering.
171 -- The function needs to call connect_signal on any inputs, so that
172 -- it gets updated video data for the given frame. (You are allowed
173 -- to switch which input your input is getting from between frames,
174 -- but not calling connect_signal results in undefined behavior.)
175 -- If you want to change any parameters in the chain, this is also
178 -- NOTE: The chain returned must be finalized with the Y'CbCr flag
179 -- if and only if num==0.
180 function get_chain(num, t, width, height)
181 if num == 0 then -- Live.
182 if live_signal_num == 0 or live_signal_num == 1 then -- Plain inputs.
184 simple_chain_hq_input:connect_signal(live_signal_num)
186 return simple_chain_hq, prepare
189 -- SBS code (live_signal_num == 2).
190 if t > zoom_end and zoom_dst == 1.0 then
191 -- Special case: Show only the single image on screen.
193 simple_chain_hq_input:connect_signal(0)
195 return simple_chain_hq, prepare
198 if t < zoom_start then
199 prepare_sbs_chain(main_chain_hq, zoom_src, width, height)
200 elseif t > zoom_end then
201 prepare_sbs_chain(main_chain_hq, zoom_dst, width, height)
203 local tt = (t - zoom_start) / (zoom_end - zoom_start)
205 tt = math.sin(tt * 3.14159265358 * 0.5)
206 prepare_sbs_chain(main_chain_hq, zoom_src + (zoom_dst - zoom_src) * tt, width, height)
209 return main_chain_hq.chain, prepare
211 if num == 1 then -- Preview.
212 num = preview_signal_num + 2
216 simple_chain_lq_input:connect_signal(0)
218 return simple_chain_lq, prepare
222 simple_chain_lq_input:connect_signal(1)
224 return simple_chain_lq, prepare
228 prepare_sbs_chain(main_chain_lq, 0.0, width, height)
230 return main_chain_lq.chain, prepare
234 function place_rectangle(resample_effect, resize_effect, padding_effect, x0, y0, x1, y1, screen_width, screen_height)
241 if x0 > screen_width or x1 < 0.0 or y0 > screen_height or y1 < 0.0 then
242 resample_effect:set_int("width", 1)
243 resample_effect:set_int("height", 1)
244 resample_effect:set_float("zoom_x", screen_width)
245 resample_effect:set_float("zoom_y", screen_height)
246 padding_effect:set_int("left", screen_width + 100)
247 padding_effect:set_int("top", screen_height + 100)
251 -- Clip. (TODO: Clip on upper/left sides, too.)
252 if x1 > screen_width then
253 srcx1 = (screen_width - x0) / (x1 - x0)
256 if y1 > screen_height then
257 srcy1 = (screen_height - y0) / (y1 - y0)
261 if resample_effect ~= nil then
262 -- High-quality resampling.
263 local x_subpixel_offset = x0 - math.floor(x0)
264 local y_subpixel_offset = y0 - math.floor(y0)
266 -- Resampling must be to an integral number of pixels. Round up,
267 -- and then add an extra pixel so we have some leeway for the border.
268 local width = math.ceil(x1 - x0) + 1
269 local height = math.ceil(y1 - y0) + 1
270 resample_effect:set_int("width", width)
271 resample_effect:set_int("height", height)
273 -- Correct the discrepancy with zoom. (This will leave a small
274 -- excess edge of pixels and subpixels, which we'll correct for soon.)
275 local zoom_x = (x1 - x0) / (width * (srcx1 - srcx0))
276 local zoom_y = (y1 - y0) / (height * (srcy1 - srcy0))
277 resample_effect:set_float("zoom_x", zoom_x)
278 resample_effect:set_float("zoom_y", zoom_y)
279 resample_effect:set_float("zoom_center_x", 0.0)
280 resample_effect:set_float("zoom_center_y", 0.0)
282 -- Padding must also be to a whole-pixel offset.
283 padding_effect:set_int("left", math.floor(x0))
284 padding_effect:set_int("top", math.floor(y0))
286 -- Correct _that_ discrepancy by subpixel offset in the resampling.
287 resample_effect:set_float("left", -x_subpixel_offset / zoom_x)
288 resample_effect:set_float("top", -y_subpixel_offset / zoom_y)
290 -- Finally, adjust the border so it is exactly where we want it.
291 padding_effect:set_float("border_offset_left", x_subpixel_offset)
292 padding_effect:set_float("border_offset_right", x1 - (math.floor(x0) + width))
293 padding_effect:set_float("border_offset_top", y_subpixel_offset)
294 padding_effect:set_float("border_offset_bottom", y1 - (math.floor(y0) + height))
296 -- Lower-quality simple resizing.
297 local width = round(x1 - x0)
298 local height = round(y1 - y0)
299 resize_effect:set_int("width", width)
300 resize_effect:set_int("height", height)
302 -- Padding must also be to a whole-pixel offset.
303 padding_effect:set_int("left", math.floor(x0))
304 padding_effect:set_int("top", math.floor(y0))
308 -- This is broken, of course (even for positive numbers), but Lua doesn't give us access to real rounding.
310 return math.floor(x + 0.5)
313 function prepare_sbs_chain(chain, t, screen_width, screen_height)
314 chain.input0.input:connect_signal(0)
315 chain.input1.input:connect_signal(1)
317 -- First input is positioned (16,48) from top-left.
318 local width0 = round(848 * screen_width/1280.0)
319 local height0 = round(width0 * 9.0 / 16.0)
321 local top0 = 48 * screen_height/720.0
322 local left0 = 16 * screen_width/1280.0
323 local bottom0 = top0 + height0
324 local right0 = left0 + width0
326 -- Second input is positioned (16,48) from the bottom-right.
327 local width1 = 384 * screen_width/1280.0
328 local height1 = 216 * screen_height/720.0
330 local bottom1 = screen_height - 48 * screen_height/720.0
331 local right1 = screen_width - 16 * screen_width/1280.0
332 local top1 = bottom1 - height1
333 local left1 = right1 - width1
335 -- Interpolate between the fullscreen and side-by-side views.
336 local scale0 = 1.0 + t * (1280.0 / 848.0 - 1.0)
337 local tx0 = 0.0 + t * (-left0 * scale0)
338 local ty0 = 0.0 + t * (-top0 * scale0)
340 top0 = top0 * scale0 + ty0
341 bottom0 = bottom0 * scale0 + ty0
342 left0 = left0 * scale0 + tx0
343 right0 = right0 * scale0 + tx0
345 top1 = top1 * scale0 + ty0
346 bottom1 = bottom1 * scale0 + ty0
347 left1 = left1 * scale0 + tx0
348 right1 = right1 * scale0 + tx0
349 place_rectangle(chain.input0.resample_effect, chain.input0.resize_effect, chain.input0.padding_effect, left0, top0, right0, bottom0, screen_width, screen_height)
350 place_rectangle(chain.input1.resample_effect, chain.input1.resize_effect, chain.input1.padding_effect, left1, top1, right1, bottom1, screen_width, screen_height)