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- Committer: Josh C
- Date: 2013-03-16 19:31:02 UTC
- Revision ID: josh@9ix.org-20130316193102-68imraus0srbj653
don't go off the edge
- files added:
- build.sh
- data
- zoetrope/input
- files removed:
- zoetrope/core/gamepad.lua
- files modified:
- zoetrope/core/app.lua
added
removed
zoetrope/sprites/map.lua
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-- set bounds
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self.width = #self.map[1] * self.spriteWidth
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self.height = #self.map * self.spriteHeight
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self.width = #self.map * self.spriteWidth
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self.height = #self.map[1] * self.spriteHeight
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return self
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end,
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return self
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end,
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-- Method: subcollide
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-- This acts as a wrapper to multiple collide() calls, as if
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-- there really were all the sprites in their particular positions.
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-- This is much more useful than Map:collide(), which simply checks
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-- if a sprite or group is touching the map at all.
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--
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-- Arguments:
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-- other - other <Sprite> or <Group>
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--
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-- Returns:
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-- boolean, whether any collision was detected
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subcollide = function (self, other)
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local hit = false
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local others
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if other.sprites then
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others = other.sprites
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else
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others = { other }
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end
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for _, othSpr in pairs(others) do
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if othSpr.solid then
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if othSpr.sprites then
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-- recurse into subgroups
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-- order is important here to avoid short-circuiting inappopriately
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hit = self:subcollide(othSpr.sprites) or hit
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else
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local startX, startY = self:pixelToMap(othSpr.x - self.x, othSpr.y - self.y)
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local endX, endY = self:pixelToMap(othSpr.x + othSpr.width - self.x,
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othSpr.y + othSpr.height - self.y)
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local x, y
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for x = startX, endX do
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for y = startY, endY do
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local spr = self.sprites[self.map[x][y]]
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if spr and spr.solid then
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-- position our map sprite as if it were onscreen
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spr.x = self.x + (x - 1) * self.spriteWidth
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spr.y = self.y + (y - 1) * self.spriteHeight
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hit = spr:collide(othSpr) or hit
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end
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end
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end
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end
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end
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end
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return hit
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end,
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-- Method: subdisplace
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-- This acts as a wrapper to multiple displace() calls, as if
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-- there really were all the sprites in their particular positions.
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-- This is much more useful than Map:displace(), which pushes a sprite or group
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-- so that it does not touch the map in its entirety.
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--
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-- Arguments:
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-- other - other <Sprite> or <Group> to displace
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-- xHint - force horizontal displacement in one direction, uses direction constants
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-- yHint - force vertical displacement in one direction, uses direction constants
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--
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-- Returns:
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-- nothing
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subdisplace = function (self, other, xHint, yHint)
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local others
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if other.sprites then
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others = other.sprites
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else
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others = { other }
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end
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for _, othSpr in pairs(others) do
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if othSpr.solid then
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if othSpr.sprites then
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-- recurse into subgroups
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-- order is important here to avoid short-circuiting inappopriately
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self:subdisplace(othSpr.sprites)
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else
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-- determine sprites we might intersect with
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local startX, startY = self:pixelToMap(othSpr.x - self.x, othSpr.y - self.y)
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local endX, endY = self:pixelToMap(othSpr.x + othSpr.width - self.x,
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othSpr.y + othSpr.height - self.y)
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local hit = true
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local loops = 0
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-- We displace the target sprite along the axis that would satisfy the
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-- most map sprites, but at the minimum distance for all of them.
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-- xVotes and yVotes track which axis should be used; this is a
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-- proportional vote, with sprites that have large amounts of overlap
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-- getting more of a chance to overrule the others. We run this loop
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-- repeatedly to make sure we end up with the target sprite not overlapping
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-- anything in the map.
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--
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-- This is based on the technique described at:
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-- http://go.colorize.net/xna/2d_collision_response_xna/
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while hit and loops < 3 do
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hit = false
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loops = loops + 1
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local xVotes, yVotes = 0, 0
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local minChangeX, minChangeY, absMinChangeX, absMinChangeY
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local origX, origY = othSpr.x, othSpr.y
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for x = startX, endX do
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for y = startY, endY do
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local spr = self.sprites[self.map[x][y]]
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if spr and spr.solid then
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-- position our map sprite as if it were onscreen
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spr.x = self.x + (x - 1) * self.spriteWidth
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spr.y = self.y + (y - 1) * self.spriteHeight
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-- displace and check to see if this displacement
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-- would result in a smaller shift than any so far
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spr:displace(othSpr)
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local xChange = othSpr.x - origX
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local yChange = othSpr.y - origY
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if xChange ~= 0 then
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xVotes = xVotes + math.abs(xChange)
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hit = true
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if not minChangeX or math.abs(xChange) < absMinChangeX then
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minChangeX = xChange
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absMinChangeX = math.abs(xChange)
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end
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end
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if yChange ~= 0 then
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yVotes = yVotes + math.abs(yChange)
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hit = true
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if not minChangeY or math.abs(yChange) < absMinChangeY then
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minChangeY = yChange
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absMinChangeY = math.abs(yChange)
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end
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end
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-- restore sprite to original position
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othSpr.x = origX
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othSpr.y = origY
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end
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end
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end
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if hit then
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if xVotes > 0 and xVotes > yVotes then
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othSpr.x = othSpr.x + minChangeX
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elseif yVotes > 0 then
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othSpr.y = othSpr.y + minChangeY
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end
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end
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end
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end
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end
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end
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end,
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-- Method: getMapSize
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-- Returns the size of the map in sprites.
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-- Returns the size of the map in map coordinates.
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--
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-- Arguments:
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-- none
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end
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end,
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-- Method: pixelToMap
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-- Converts pixels to map coordinates.
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--
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-- Arguments:
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-- x - x coordinate in pixels
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-- y - y coordinate in pixels
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-- clamp - clamp to map bounds? defaults to true
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--
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-- Returns:
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-- x, y map coordinates
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pixelToMap = function (self, x, y, clamp)
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if type(clamp) == 'nil' then clamp = true end
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-- remember, Lua tables start at index 1
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local mapX = math.floor(x / self.spriteWidth) + 1
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local mapY = math.floor(y / self.spriteHeight) + 1
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-- clamp to map bounds
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if clamp then
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if mapX < 1 then mapX = 1 end
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if mapY < 1 then mapY = 1 end
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if mapX > #self.map then mapX = #self.map end
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if mapY > #self.map[1] then mapY = #self.map[1] end
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end
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return mapX, mapY
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end,
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-- Method: spriteAtMap
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-- Returns the sprite at a given set of map coordinates, with
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-- the correct pixel position for that sprite. Remember that
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-- sprites in maps are shared, so any changes you make to one
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-- sprite will carry over to all instances of that sprite in the map.
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--
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-- Arguments:
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-- x - x coordinate in map units
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-- y - y coordinate in map units
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--
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-- Returns:
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-- <Sprite> instance. If no sprite is present at these
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-- coordinates, the method returns nil.
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spriteAtMap = function (self, x, y)
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if self.map[x] and self.map[x][y] then
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local spr = self.sprites[self.map[x][y]]
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if spr then
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spr.x = (x - 1) * self.spriteWidth
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spr.y = (y - 1) * self.spriteHeight
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return spr
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end
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elseif STRICT then
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print('Warning: asked for map sprite at ' .. x .. ', ' .. y ' but map isn\'t that big')
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end
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end,
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-- Method: spriteAtPixel
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-- Returns the sprite at a given set of pixel coordinates, with
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-- the correct pixel position for that sprite. Remember that
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-- sprites in maps are shared, so any changes you make to one
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-- sprite will carry over to all instances of that sprite in the map.
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--
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-- Arguments:
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-- x - x coordinate in pixels
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-- y - y coordinate in pixels
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--
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-- Returns:
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-- <Sprite> instance. If no sprite is present at these
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-- coordinates, the method returns nil.
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spriteAtPixel = function (self, x, y)
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return self:spriteAtMap((x - 1) * self.spriteWidth, (y - 1) * self.spriteHeight)
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end,
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-- This overrides a method in <Sprite>, passing along
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-- collidedWith() calls to all sprites in the map touching a
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-- sprite.
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--
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-- Arguments:
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-- other - other <Sprite>
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--
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-- Returns:
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-- nothing
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collidedWith = function (self, other)
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local spriteWidth = self.spriteWidth
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local spriteHeight = self.spriteHeight
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local startX, startY = self:pixelToMap(other.x - self.x, other.y - self.y)
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local endX, endY = self:pixelToMap(other.x + other.width - self.x,
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other.y + other.height - self.y)
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-- collect collisions against sprites
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local collisions = {}
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for x = startX, endX do
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for y = startY, endY do
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local spr = self.sprites[self.map[x][y]]
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if spr and spr.solid then
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local sprX = self.x + (x - 1) * spriteWidth
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local sprY = self.y + (y - 1) * spriteHeight
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local xOverlap, yOverlap = other:overlap(sprX, sprY, spriteWidth, spriteHeight)
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if xOverlap ~= 0 or yOverlap ~= 0 then
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table.insert(collisions, { area = xOverlap * yOverlap, x = xOverlap, y = yOverlap,
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a = spr, ax = sprX, ay = sprY })
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end
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end
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end
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end
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-- sort as usual and pass off collidedWith() calls
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table.sort(collisions, Collision.sortCollisions)
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for _, col in ipairs(collisions) do
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col.a.x, col.a.y = col.ax, col.ay
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col.a:collidedWith(other, col.x, col.y)
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other:collidedWith(col.a, col.x, col.y)
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end
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end,
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-- this is here mainly for completeness; it's better to specify displacement
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-- in individual map sprites
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displace = function (self, other, xHint, yHint)
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if not self.solid or self == other or not other.solid then return end
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if STRICT then assert(other:instanceOf(Sprite), 'asked to displace a non-sprite') end
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local spriteWidth = self.spriteWidth
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local spriteHeight = self.spriteHeight
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local startX, startY = self:pixelToMap(other.x - self.x, other.y - self.y)
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local endX, endY = self:pixelToMap(other.x + other.width - self.x,
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other.y + other.height - self.y)
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-- collect collisions against sprites
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local collisions = {}
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for x = startX, endX do
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for y = startY, endY do
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local spr = self.sprites[self.map[x][y]]
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if spr and spr.solid then
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local sprX = self.x + (x - 1) * spriteWidth
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local sprY = self.y + (y - 1) * spriteHeight
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local xOverlap, yOverlap = other:overlap(sprX, sprY, spriteWidth, spriteHeight)
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if xOverlap ~= 0 or yOverlap ~= 0 then
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table.insert(collisions, { area = xOverlap * yOverlap, x = xOverlap, y = yOverlap,
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a = spr, ax = sprX, ay = sprY })
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end
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end
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end
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end
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-- sort as usual and displace
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table.sort(collisions, Collision.sortCollisions)
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for _, col in ipairs(collisions) do
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col.a.x, col.a.y = col.ax, col.ay
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col.a:displace(other)
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end
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end,
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draw = function (self, x, y)
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-- lock our x/y coordinates to integers
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-- to avoid gaps in the tiles
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sprite:draw(coords[1], coords[2])
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end
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end
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Sprite.draw(self)
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end,
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-- Method: pixelToMap
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-- Converts pixels to map coordinates.
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--
378
-- Arguments:
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-- x - x coordinate in pixels
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-- y - y coordinate in pixels
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-- clamp - clamp to map bounds? defaults to true
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--
383
-- Returns:
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-- x, y map coordinates
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pixelToMap = function (self, x, y, clamp)
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if type(clamp) == 'nil' then clamp = true end
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-- remember, Lua tables start at index 1
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local mapX = math.floor(x / self.spriteWidth) + 1
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local mapY = math.floor(y / self.spriteHeight) + 1
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-- clamp to map bounds
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if clamp then
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if mapX < 1 then mapX = 1 end
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if mapY < 1 then mapY = 1 end
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if mapX > #self.map then mapX = #self.map end
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if mapY > #self.map[1] then mapY = #self.map[1] end
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end
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return mapX, mapY
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end,
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-- makes sure all sprites receive startFrame messages
Loggerhead is a web-based interface for Breezy
Version: 2.0.1