Hello guys! I tried to reproduce the intro from Zelda Roth and got this error: line 27:31 >
Error: In maps/intro: [string:"maps/intro.lua"]:33: attempt to index a nil value
The code:
-- Frescos.
local frescos = {}
for i = 1, 5 do
frescos[i] = sol.surface.create("menus/intro/intro" .. i .. ".png")
frescos[i]:set_xy(0, 16)
end
It's the same code maked by Christopho's, Just change quantitis on for. What's wrong with it?
The error is in line 33 of your script (could you post the code of all the script?).
It says that you are trying to index (access an attribute) of a nil variable (the variable has nothing attached so you cannot access the attribute and hence you get an error; you need a list to access an attribute).
local map = ...
local game = map:get_game()
-- Intro.
local map_width, map_height = map:get_size()
game:set_hud_enabled(false)
hero:set_enabled(false)
-- Scrolling backgrounds.
local bg1_img = sol.surface.create("menus/intro/bg1.png")
local bg1_width, bg1_height = bg1_img:get_size()
local bg1_xy = {}
local bg1_movement = sol.movement.create("straight")
bg1_movement:set_angle(3 * math.pi / 4)
bg1_movement:set_speed(32)
bg1_movement:start(bg1_xy)
local bg2_img = sol.surface.create("menus/intro/bg2.png")
local bg2_width, bg2_height = bg2_img:get_size()
local bg2_xy = {}
local bg2_movement = sol.movement.create("straight")
bg2_movement:set_angle(math.pi / 4)
bg2_movement:set_speed(32)
bg2_movement:start(bg2_xy)
-- Frescos.
local frescos = {}
for i = 1, 4 do
frescos[i] = sol.surface.create("menus/intro/intro" .. i .. ".png")
frescos[i]:set_xy(0, 16)
end
local fresco_index = 0 -- Index of the current fresco.
-- Dialog.
local dialog_background_img = sol.surface.create(256, 64)
dialog_background_img:set_xy(32, 160)
dialog_background_img:fill_color({255, 255, 128, 128})
function bg1_movement:on_position_changed(x, y)
if y <= -bg1_height then
bg1_movement:set_xy(0, 0)
end
end
function bg2_movement:on_position_changed(x, y)
if y <= -bg2_height then
bg2_movement:set_xy(0, 0)
end
end
local function next_fresco()
if fresco_index < #frescos then
fresco_index = fresco_index + 1
game:start_dialog("intro.fresco_" .. fresco_index, next_fresco)
else
-- Restore usual settings.
game:get_dialog_box():set_style("box")
game:get_dialog_box():set_position("bottom")
hero:unfreeze()
-- Go to the first map.
-- hero:teleport("houses/link_house", "from_intro")
end
end
function map:on_started()
game:get_dialog_box():set_style("empty")
game:get_dialog_box():set_position({ x = 32, y = 160})
next_fresco()
end
function map:on_opening_transition_finished()
hero:freeze()
end
function map:on_draw(dst_surface)
-- Scrolling backgrounds.
for y = -bg2_height, map_height + bg2_height, bg2_height do
for x = -bg2_width, map_width + bg2_width, bg2_width do
bg2_img:draw(dst_surface, bg2_xy.x + x, bg2_xy.y + y)
end
end
for y = -bg1_height, map_height + bg1_height, bg1_height do
for x = -bg1_width, map_width + bg1_width, bg1_width do
bg1_img:draw(dst_surface, bg1_xy.x + x, bg1_xy.y + y)
end
end
-- Fresco.
if fresco_index > 0 and fresco_index <= #frescos then
frescos[fresco_index]:draw(dst_surface)
end
-- Dialog box background.
dialog_background_img:draw(dst_surface)
end
Thanks.
Ok, the error is exactly in line:
frescos[i]:set_xy(0, 16)
which means that frescos[i] is nil, or in other words, your image has not been created in the previous line:
frescos[i] = sol.surface.create("menus/intro/intro" .. i .. ".png")
which in turn means that the id of the image (this one: "menus/intro/intro" .. i .. ".png") is not correct.
(The image has not been created by the engine since that file does not exist; there is something wrong in that string.)
In most case, if frescos returns nil, this is because your surface isn't created because the file has not been found
Thank you guys! xD
--------- @Edit:
How can I reproduce something like in this video: 1:34 - 1:38
https://www.youtube.com/watch?v=3Jm8_1zoZtw&list=PLaT85v0g5RS6Lshz4RUNGF8bpNqZHsmuM
The camera approaches on point of image on the screen in game intro. How to make it?
To do that zoom with that camera angle we may need something like this: https://en.wikipedia.org/wiki/Mode_7
Or maybe just a normal zoom (maybe this can already be done).
I don't remember if there are already requests for these features in github.
Something like this?:
https://github.com/Rakoonic/Mode-7/blob/master/Mode%207/code/menu.lua
https://github.com/Rakoonic/Mode-7/blob/master/Mode%207/code/setup.lua
https://github.com/Rakoonic/Mode-7/blob/master/Mode%207/libs/globals.lua
https://github.com/Rakoonic/Mode-7/blob/master/Mode%207/code/game.lua
Solarus Engine support the libraries from Mode 7 graphics?
Probably, but I am not sure if that is the same thing, and also I don't know which license has that code (it could be incompatible with GPL).
Anyway, you cannot directly add a library without coding something in the engine (the C++ part).