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 transition_start = -2.0
12 local transition_end = -1.0
18 local live_signal_num = 0
19 local preview_signal_num = 1
21 -- The main live chain.
22 function make_sbs_chain(hq)
23 local chain = EffectChain.new(16, 9)
24 local input0 = chain:add_live_input()
25 input0:connect_signal(0)
26 local input1 = chain:add_live_input()
27 input1:connect_signal(1)
29 local resample_effect = nil
30 local resize_effect = nil
32 resample_effect = chain:add_effect(ResampleEffect.new(), input0)
34 resize_effect = chain:add_effect(ResizeEffect.new(), input0)
37 local padding_effect = chain:add_effect(IntegralPaddingEffect.new())
38 padding_effect:set_vec4("border_color", 0.0, 0.0, 0.0, 1.0)
40 local resample2_effect = nil
41 local resize2_effect = nil
43 resample2_effect = chain:add_effect(ResampleEffect.new(), input1)
45 resize2_effect = chain:add_effect(ResizeEffect.new(), input1)
47 -- Effect *saturation_effect = chain->add_effect(new SaturationEffect())
48 -- CHECK(saturation_effect->set_float("saturation", 0.3f))
49 local wb_effect = chain:add_effect(WhiteBalanceEffect.new())
50 wb_effect:set_float("output_color_temperature", 3500.0)
51 local padding2_effect = chain:add_effect(IntegralPaddingEffect.new())
53 chain:add_effect(OverlayEffect.new(), padding_effect, padding2_effect)
60 resample_effect = resample_effect,
61 resize_effect = resize_effect,
62 padding_effect = padding_effect
66 resample_effect = resample2_effect,
67 resize_effect = resize2_effect,
68 padding_effect = padding2_effect
73 local main_chain_hq = make_sbs_chain(true)
74 local main_chain_lq = make_sbs_chain(false)
76 -- A chain to fade between two inputs (live chain only)
77 local fade_chain_hq = EffectChain.new(16, 9)
78 local fade_chain_hq_input0 = fade_chain_hq:add_live_input()
79 local fade_chain_hq_input1 = fade_chain_hq:add_live_input()
80 fade_chain_hq_input0:connect_signal(0)
81 fade_chain_hq_input1:connect_signal(1)
82 local fade_chain_mix_effect = fade_chain_hq:add_effect(MixEffect.new(), fade_chain_hq_input0, fade_chain_hq_input1)
83 fade_chain_hq:finalize(true)
85 -- A chain to show a single input on screen (HQ version).
86 local simple_chain_hq = EffectChain.new(16, 9)
87 local simple_chain_hq_input = simple_chain_hq:add_live_input()
88 simple_chain_hq_input:connect_signal(0) -- First input card. Can be changed whenever you want.
89 simple_chain_hq:finalize(true)
91 -- A chain to show a single input on screen (LQ version).
92 local simple_chain_lq = EffectChain.new(16, 9)
93 local simple_chain_lq_input = simple_chain_lq:add_live_input()
94 simple_chain_lq_input:connect_signal(0) -- First input card. Can be changed whenever you want.
95 simple_chain_lq:finalize(false)
97 -- Returns the number of outputs in addition to the live (0) and preview (1).
98 -- Called only once, at the start of the program.
99 function num_channels()
103 function finish_transitions(t)
104 -- If live is 2 (SBS) but de-facto single, make it so.
105 if live_signal_num == 2 and t >= transition_end and zoom_dst == 1.0 then
109 -- If live is 3 (fade) but de-facto single, make it so.
110 if live_signal_num == 3 and t >= transition_end and fade_dst == 1.0 then
113 if live_signal_num == 3 and t >= transition_end and fade_dst == 0.0 then
118 -- Called every frame.
119 function get_transitions(t)
120 finish_transitions(t)
122 if live_signal_num == preview_signal_num then
126 if live_signal_num == 2 and t >= transition_start and t <= transition_end then
131 if (live_signal_num == 0 and preview_signal_num == 1) or
132 (live_signal_num == 1 and preview_signal_num == 0) then
133 return {"Cut", "", "Fade"}
136 if live_signal_num == 2 and preview_signal_num == 1 then
137 -- Zoom-out not supported here yet.
141 if live_signal_num == 2 and preview_signal_num == 0 then
142 return {"Cut", "Zoom in"}
143 elseif live_signal_num == 0 and preview_signal_num == 2 then
144 return {"Cut", "Zoom out"}
150 function transition_clicked(num, t)
153 if live_signal_num == 3 then
154 -- Ongoing fade; finish it immediately.
155 finish_transitions(transition_end)
158 local temp = live_signal_num
159 live_signal_num = preview_signal_num
160 preview_signal_num = temp
162 if live_signal_num == 2 then
163 -- Just cut to SBS, we need to reset any zooms.
166 transition_start = -2.0
167 transition_end = -1.0
172 finish_transitions(t)
174 if live_signal_num == preview_signal_num then
179 if (live_signal_num == 0 and preview_signal_num == 1) or
180 (live_signal_num == 1 and preview_signal_num == 0) then
181 -- We can't zoom between these. Just make a cut.
182 io.write("Cutting from " .. live_signal_num .. " to " .. live_signal_num .. "\n")
183 local temp = live_signal_num
184 live_signal_num = preview_signal_num
185 preview_signal_num = temp
189 if live_signal_num == 2 and preview_signal_num == 1 then
190 io.write("NOT SUPPORTED YET\n")
194 if live_signal_num == 2 and preview_signal_num == 0 then
195 -- Zoom in from SBS to single.
197 transition_end = t + 1.0
200 preview_signal_num = 2
201 elseif live_signal_num == 0 and preview_signal_num == 2 then
202 -- Zoom out from single to SBS.
204 transition_end = t + 1.0
207 preview_signal_num = 0
211 finish_transitions(t)
214 if live_signal_num == 0 and preview_signal_num == 1 then
216 transition_end = t + 1.0
219 preview_signal_num = 0
221 elseif live_signal_num == 1 and preview_signal_num == 0 then
223 transition_end = t + 1.0
226 preview_signal_num = 1
229 -- Fades involving SBS are ignored (we have no chain for it).
234 function channel_clicked(num)
235 preview_signal_num = num
238 -- Called every frame. Get the chain for displaying at input <num>,
239 -- where 0 is live, 1 is preview, 2 is the first channel to display
240 -- in the bottom bar, and so on up to num_channels()+1. t is the
241 -- current time in seconds. width and height are the dimensions of
242 -- the output, although you can ignore them if you don't need them
243 -- (they're useful if you want to e.g. know what to resample by).
245 -- You should return two objects; the chain itself, and then a
246 -- function (taking no parameters) that is run just before rendering.
247 -- The function needs to call connect_signal on any inputs, so that
248 -- it gets updated video data for the given frame. (You are allowed
249 -- to switch which input your input is getting from between frames,
250 -- but not calling connect_signal results in undefined behavior.)
251 -- If you want to change any parameters in the chain, this is also
254 -- NOTE: The chain returned must be finalized with the Y'CbCr flag
255 -- if and only if num==0.
256 function get_chain(num, t, width, height)
257 if num == 0 then -- Live.
258 if live_signal_num == 0 or live_signal_num == 1 then -- Plain inputs.
260 simple_chain_hq_input:connect_signal(live_signal_num)
262 return simple_chain_hq, prepare
263 elseif live_signal_num == 3 then -- Fade.
265 fade_chain_hq_input0:connect_signal(0)
266 fade_chain_hq_input1:connect_signal(1)
267 local tt = (t - transition_start) / (transition_end - transition_start)
274 tt = fade_src + tt * (fade_dst - fade_src)
276 fade_chain_mix_effect:set_float("strength_first", tt)
277 fade_chain_mix_effect:set_float("strength_second", 1.0 - tt)
279 return fade_chain_hq, prepare
282 -- SBS code (live_signal_num == 2).
283 if t > transition_end and zoom_dst == 1.0 then
284 -- Special case: Show only the single image on screen.
286 simple_chain_hq_input:connect_signal(0)
288 return simple_chain_hq, prepare
291 if t < transition_start then
292 prepare_sbs_chain(main_chain_hq, zoom_src, width, height)
293 elseif t > transition_end then
294 prepare_sbs_chain(main_chain_hq, zoom_dst, width, height)
296 local tt = (t - transition_start) / (transition_end - transition_start)
298 tt = math.sin(tt * 3.14159265358 * 0.5)
299 prepare_sbs_chain(main_chain_hq, zoom_src + (zoom_dst - zoom_src) * tt, width, height)
302 return main_chain_hq.chain, prepare
304 if num == 1 then -- Preview.
305 num = preview_signal_num + 2
309 simple_chain_lq_input:connect_signal(0)
311 return simple_chain_lq, prepare
315 simple_chain_lq_input:connect_signal(1)
317 return simple_chain_lq, prepare
321 prepare_sbs_chain(main_chain_lq, 0.0, width, height)
323 return main_chain_lq.chain, prepare
327 function place_rectangle(resample_effect, resize_effect, padding_effect, x0, y0, x1, y1, screen_width, screen_height)
334 if x0 > screen_width or x1 < 0.0 or y0 > screen_height or y1 < 0.0 then
335 resample_effect:set_int("width", 1)
336 resample_effect:set_int("height", 1)
337 resample_effect:set_float("zoom_x", screen_width)
338 resample_effect:set_float("zoom_y", screen_height)
339 padding_effect:set_int("left", screen_width + 100)
340 padding_effect:set_int("top", screen_height + 100)
344 -- Clip. (TODO: Clip on upper/left sides, too.)
345 if x1 > screen_width then
346 srcx1 = (screen_width - x0) / (x1 - x0)
349 if y1 > screen_height then
350 srcy1 = (screen_height - y0) / (y1 - y0)
354 if resample_effect ~= nil then
355 -- High-quality resampling.
356 local x_subpixel_offset = x0 - math.floor(x0)
357 local y_subpixel_offset = y0 - math.floor(y0)
359 -- Resampling must be to an integral number of pixels. Round up,
360 -- and then add an extra pixel so we have some leeway for the border.
361 local width = math.ceil(x1 - x0) + 1
362 local height = math.ceil(y1 - y0) + 1
363 resample_effect:set_int("width", width)
364 resample_effect:set_int("height", height)
366 -- Correct the discrepancy with zoom. (This will leave a small
367 -- excess edge of pixels and subpixels, which we'll correct for soon.)
368 local zoom_x = (x1 - x0) / (width * (srcx1 - srcx0))
369 local zoom_y = (y1 - y0) / (height * (srcy1 - srcy0))
370 resample_effect:set_float("zoom_x", zoom_x)
371 resample_effect:set_float("zoom_y", zoom_y)
372 resample_effect:set_float("zoom_center_x", 0.0)
373 resample_effect:set_float("zoom_center_y", 0.0)
375 -- Padding must also be to a whole-pixel offset.
376 padding_effect:set_int("left", math.floor(x0))
377 padding_effect:set_int("top", math.floor(y0))
379 -- Correct _that_ discrepancy by subpixel offset in the resampling.
380 resample_effect:set_float("left", -x_subpixel_offset / zoom_x)
381 resample_effect:set_float("top", -y_subpixel_offset / zoom_y)
383 -- Finally, adjust the border so it is exactly where we want it.
384 padding_effect:set_float("border_offset_left", x_subpixel_offset)
385 padding_effect:set_float("border_offset_right", x1 - (math.floor(x0) + width))
386 padding_effect:set_float("border_offset_top", y_subpixel_offset)
387 padding_effect:set_float("border_offset_bottom", y1 - (math.floor(y0) + height))
389 -- Lower-quality simple resizing.
390 local width = round(x1 - x0)
391 local height = round(y1 - y0)
392 resize_effect:set_int("width", width)
393 resize_effect:set_int("height", height)
395 -- Padding must also be to a whole-pixel offset.
396 padding_effect:set_int("left", math.floor(x0))
397 padding_effect:set_int("top", math.floor(y0))
401 -- This is broken, of course (even for positive numbers), but Lua doesn't give us access to real rounding.
403 return math.floor(x + 0.5)
406 function prepare_sbs_chain(chain, t, screen_width, screen_height)
407 chain.input0.input:connect_signal(0)
408 chain.input1.input:connect_signal(1)
410 -- First input is positioned (16,48) from top-left.
411 local width0 = round(848 * screen_width/1280.0)
412 local height0 = round(width0 * 9.0 / 16.0)
414 local top0 = 48 * screen_height/720.0
415 local left0 = 16 * screen_width/1280.0
416 local bottom0 = top0 + height0
417 local right0 = left0 + width0
419 -- Second input is positioned (16,48) from the bottom-right.
420 local width1 = 384 * screen_width/1280.0
421 local height1 = 216 * screen_height/720.0
423 local bottom1 = screen_height - 48 * screen_height/720.0
424 local right1 = screen_width - 16 * screen_width/1280.0
425 local top1 = bottom1 - height1
426 local left1 = right1 - width1
428 -- Interpolate between the fullscreen and side-by-side views.
429 local scale0 = 1.0 + t * (1280.0 / 848.0 - 1.0)
430 local tx0 = 0.0 + t * (-left0 * scale0)
431 local ty0 = 0.0 + t * (-top0 * scale0)
433 top0 = top0 * scale0 + ty0
434 bottom0 = bottom0 * scale0 + ty0
435 left0 = left0 * scale0 + tx0
436 right0 = right0 * scale0 + tx0
438 top1 = top1 * scale0 + ty0
439 bottom1 = bottom1 * scale0 + ty0
440 left1 = left1 * scale0 + tx0
441 right1 = right1 * scale0 + tx0
442 place_rectangle(chain.input0.resample_effect, chain.input0.resize_effect, chain.input0.padding_effect, left0, top0, right0, bottom0, screen_width, screen_height)
443 place_rectangle(chain.input1.resample_effect, chain.input1.resize_effect, chain.input1.padding_effect, left1, top1, right1, bottom1, screen_width, screen_height)