git.sesse.net Git - nageru/blob - theme.lua

   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.
   5 --
   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")
  10
  11 local transition_start = -2.0
  12 local transition_end = -1.0
  13 local zoom_src = 0.0
  14 local zoom_dst = 1.0
  15 local fade_src = 0.0
  16 local fade_dst = 1.0
  17
  18 local live_signal_num = 0
  19 local preview_signal_num = 1
  20
  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)
  28
  29         local resample_effect = nil
  30         local resize_effect = nil
  31         if (hq) then
  32                 resample_effect = chain:add_effect(ResampleEffect.new(), input0)
  33         else
  34                 resize_effect = chain:add_effect(ResizeEffect.new(), input0)
  35         end
  36
  37         local padding_effect = chain:add_effect(IntegralPaddingEffect.new())
  38         padding_effect:set_vec4("border_color", 0.0, 0.0, 0.0, 1.0)
  39
  40         local resample2_effect = nil
  41         local resize2_effect = nil
  42         if (hq) then
  43                 resample2_effect = chain:add_effect(ResampleEffect.new(), input1)
  44         else
  45                 resize2_effect = chain:add_effect(ResizeEffect.new(), input1)
  46         end
  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())
  52
  53         chain:add_effect(OverlayEffect.new(), padding_effect, padding2_effect)
  54         chain:finalize(hq)
  55
  56         return {
  57                 chain = chain,
  58                 input0 = {
  59                         input = input0,
  60                         resample_effect = resample_effect,
  61                         resize_effect = resize_effect,
  62                         padding_effect = padding_effect
  63                 },
  64                 input1 = {
  65                         input = input1,
  66                         resample_effect = resample2_effect,
  67                         resize_effect = resize2_effect,
  68                         padding_effect = padding2_effect
  69                 }
  70         }
  71 end
  72
  73 local main_chain_hq = make_sbs_chain(true)
  74 local main_chain_lq = make_sbs_chain(false)
  75
  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)
  84
  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)
  90
  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)
  96
  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()
 100         return 3
 101 end
 102
 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
 106                 live_signal_num = 0
 107         end
 108
 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
 111                 live_signal_num = 0
 112         end
 113         if live_signal_num == 3 and t >= transition_end and fade_dst == 0.0 then
 114                 live_signal_num = 1
 115         end
 116 end
 117
 118 -- Called every frame.
 119 function get_transitions(t)
 120         finish_transitions(t)
 121
 122         if live_signal_num == preview_signal_num then
 123                 return {}
 124         end
 125
 126         if live_signal_num == 2 and t >= transition_start and t <= transition_end then
 127                 -- Zoom in progress.
 128                 return {"Cut"}
 129         end
 130
 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"}
 134         end
 135
 136         if live_signal_num == 2 and preview_signal_num == 1 then
 137                 -- Zoom-out not supported here yet.
 138                 return {"Cut"}
 139         end
 140
 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"}
 145         end
 146
 147         return {"Cut"}
 148 end
 149
 150 function transition_clicked(num, t)
 151         if num == 0 then
 152                 -- Cut.
 153                 if live_signal_num == 3 then
 154                         -- Ongoing fade; finish it immediately.
 155                         finish_transitions(transition_end)
 156                 end
 157
 158                 local temp = live_signal_num
 159                 live_signal_num = preview_signal_num
 160                 preview_signal_num = temp
 161
 162                 if live_signal_num == 2 then
 163                         -- Just cut to SBS, we need to reset any zooms.
 164                         zoom_src = 1.0
 165                         zoom_dst = 0.0
 166                         transition_start = -2.0
 167                         transition_end = -1.0
 168                 end
 169         elseif num == 1 then
 170                 -- Zoom.
 171
 172                 finish_transitions(t)
 173
 174                 if live_signal_num == preview_signal_num then
 175                         -- Nothing to do.
 176                         return
 177                 end
 178
 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
 186                         return
 187                 end
 188
 189                 if live_signal_num == 2 and preview_signal_num == 1 then
 190                         io.write("NOT SUPPORTED YET\n")
 191                         return
 192                 end
 193
 194                 if live_signal_num == 2 and preview_signal_num == 0 then
 195                         -- Zoom in from SBS to single.
 196                         transition_start = t
 197                         transition_end = t + 1.0
 198                         zoom_src = 0.0
 199                         zoom_dst = 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.
 203                         transition_start = t
 204                         transition_end = t + 1.0
 205                         zoom_src = 1.0
 206                         zoom_dst = 0.0
 207                         preview_signal_num = 0
 208                         live_signal_num = 2
 209                 end
 210         elseif num == 2 then
 211                 finish_transitions(t)
 212
 213                 -- Fade.
 214                 if live_signal_num == 0 and preview_signal_num == 1 then
 215                         transition_start = t
 216                         transition_end = t + 1.0
 217                         fade_src = 1.0
 218                         fade_dst = 0.0
 219                         preview_signal_num = 0
 220                         live_signal_num = 3
 221                 elseif live_signal_num == 1 and preview_signal_num == 0 then
 222                         transition_start = t
 223                         transition_end = t + 1.0
 224                         fade_src = 0.0
 225                         fade_dst = 1.0
 226                         preview_signal_num = 1
 227                         live_signal_num = 3
 228                 else
 229                         -- Fades involving SBS are ignored (we have no chain for it).
 230                 end
 231         end
 232 end
 233
 234 function channel_clicked(num)
 235         preview_signal_num = num
 236 end
 237
 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).
 244 --
 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
 252 -- the right place.
 253 --
 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.
 259                         prepare = function()
 260                                 simple_chain_hq_input:connect_signal(live_signal_num)
 261                         end
 262                         return simple_chain_hq, prepare
 263                 elseif live_signal_num == 3 then  -- Fade.
 264                         prepare = function()
 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)
 268                                 if tt < 0.0 then
 269                                         tt = 0.0
 270                                 elseif tt > 1.0 then
 271                                         tt = 1.0
 272                                 end
 273
 274                                 tt = fade_src + tt * (fade_dst - fade_src)
 275
 276                                 fade_chain_mix_effect:set_float("strength_first", tt)
 277                                 fade_chain_mix_effect:set_float("strength_second", 1.0 - tt)
 278                         end
 279                         return fade_chain_hq, prepare
 280                 end
 281
 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.
 285                         prepare = function()
 286                                 simple_chain_hq_input:connect_signal(0)
 287                         end
 288                         return simple_chain_hq, prepare
 289                 end
 290                 prepare = function()
 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)
 295                         else
 296                                 local tt = (t - transition_start) / (transition_end - transition_start)
 297                                 -- Smooth it a bit.
 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)
 300                         end
 301                 end
 302                 return main_chain_hq.chain, prepare
 303         end
 304         if num == 1 then  -- Preview.
 305                 num = preview_signal_num + 2
 306         end
 307         if num == 2 then
 308                 prepare = function()
 309                         simple_chain_lq_input:connect_signal(0)
 310                 end
 311                 return simple_chain_lq, prepare
 312         end
 313         if num == 3 then
 314                 prepare = function()
 315                         simple_chain_lq_input:connect_signal(1)
 316                 end
 317                 return simple_chain_lq, prepare
 318         end
 319         if num == 4 then
 320                 prepare = function()
 321                         prepare_sbs_chain(main_chain_lq, 0.0, width, height)
 322                 end
 323                 return main_chain_lq.chain, prepare
 324         end
 325 end
 326
 327 function place_rectangle(resample_effect, resize_effect, padding_effect, x0, y0, x1, y1, screen_width, screen_height)
 328         local srcx0 = 0.0
 329         local srcx1 = 1.0
 330         local srcy0 = 0.0
 331         local srcy1 = 1.0
 332
 333         -- Cull.
 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)
 341                 return
 342         end
 343
 344         -- Clip. (TODO: Clip on upper/left sides, too.)
 345         if x1 > screen_width then
 346                 srcx1 = (screen_width - x0) / (x1 - x0)
 347                 x1 = screen_width
 348         end
 349         if y1 > screen_height then
 350                 srcy1 = (screen_height - y0) / (y1 - y0)
 351                 y1 = screen_height
 352         end
 353
 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)
 358
 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)
 365
 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)
 374
 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))
 378
 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)
 382
 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))
 388         else
 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)
 394
 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))
 398         end
 399 end
 400
 401 -- This is broken, of course (even for positive numbers), but Lua doesn't give us access to real rounding.
 402 function round(x)
 403         return math.floor(x + 0.5)
 404 end
 405
 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)
 409
 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)
 413
 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
 418
 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
 422
 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
 427
 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)
 432
 433         top0 = top0 * scale0 + ty0
 434         bottom0 = bottom0 * scale0 + ty0
 435         left0 = left0 * scale0 + tx0
 436         right0 = right0 * scale0 + tx0
 437
 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)
 444 end