Approved
Warcraft Moderator
- Joined
- Aug 10, 2018
- Messages
- 7,866
That's a really cool idea, but I wonder if at this point it's more efficient to just rely on Units?
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Special Effect Shadows
Special effects are easier to work with, more versatile, and more performant than dummy units. Therefore, once the Blz special effect natives arrived prior to Reforged launch, there wasn't really a reason anymore to represent objects such as missiles as dummy units — except that special effects don't have shadows. This is where this library comes in.
SpecialEffectShadows allows the creation of objects represented by special effects and still have them cast shadows. Shadows are represented by images. The functions to
manipulate shadow-casting effects are analogous to the default special effect natives, for example BlzSetSpecialEffectPosition -> SetShadowedEffectPosition.
All functions for which the corresponding native is safe to use asynchronously can also safely be used asynchronously.
Using special effects with shadows instead of dummy units has the advantage that they're easier to handle, you can adjust their yaw, pitch, and roll, and when making them transparent, the shadow will fade out as well. I have to still do some benchmarks to find out which one is more performant.
There are two versions: The standard version has its own set of functions to move the shadowed special effects. The alternate version uses Hook to also affect the shadow on a native call, if it exists. This version allows you to add shadows to effects easily without changing the functions everywhere in your code, but it makes moving special effects slightly slower.
Will make JASS/GUI versions if requested.
SpecialEffectShadows allows the creation of objects represented by special effects and still have them cast shadows. Shadows are represented by images. The functions to
manipulate shadow-casting effects are analogous to the default special effect natives, for example BlzSetSpecialEffectPosition -> SetShadowedEffectPosition.
All functions for which the corresponding native is safe to use asynchronously can also safely be used asynchronously.
Using special effects with shadows instead of dummy units has the advantage that they're easier to handle, you can adjust their yaw, pitch, and roll, and when making them transparent, the shadow will fade out as well. I have to still do some benchmarks to find out which one is more performant.
There are two versions: The standard version has its own set of functions to move the shadowed special effects. The alternate version uses Hook to also affect the shadow on a native call, if it exists. This version allows you to add shadows to effects easily without changing the functions everywhere in your code, but it makes moving special effects slightly slower.
Will make JASS/GUI versions if requested.
Lua:
if Debug then Debug.beginFile "SpecialEffectShadows" end
do
--[[
=============================================================================================================================================================
Special Effect Shadows
by Antares
Requires:
PrecomputedHeightMap (optional) https://www.hiveworkshop.com/threads/precomputed-synchronized-terrain-height-map.353477/
TotalInitialization https://www.hiveworkshop.com/threads/total-initialization.317099/
=============================================================================================================================================================
Allows the creation of objects represented by special effects that cast shadows. Shadows are represented by images. The functions to manipulate shadow-casting
effects are analogous to the default special effect natives, for example BlzSetSpecialEffectPosition -> SetShadowedEffectPosition. All functions for which the
corresponding native is safe to use asynchronously can also safely be used asynchronously.
The AddShadowedEffect function requires a path for the shadow texture. There are two preset constants: UNIT_SHADOW_PATH is the standard shadow that ground
units use. FLYER_SHADOW_PATH is the shadow that flying units use. Building shadows have a weird format and cannot be used without converting them first.
=============================================================================================================================================================
Functions
=============================================================================================================================================================
AddShadowedEffect(modelPath, x, y, shadowPath, shadowWidth, shadowHeight, xOffset, yOffset) -> effect
DestroyShadowedEffect(whichEffect)
SetShadowedEffectPosition(whichEffect, x, y, z)
SetShadowedEffectX(whichEffect, x)
SetShadowedEffectY(whichEffect, y)
SetShadowedEffectZ(whichEffect, z)
SetShadowedEffectAlpha(whichEffect, alpha) Fades the effect as well as the shadow.
=============================================================================================================================================================
Config
=============================================================================================================================================================
]]
local SUN_ZENITH_ANGLE = 45 ---@type number
--Determines the direction of the sun light in degrees. 90 = sun at the zenith. Does not affect shadow shape.
local SUN_AZIMUTH_ANGLE = 45 ---@type number
--Determines the direction of the sun light in degrees. 0 = shadows cast in positive x-direction. Does not affect shadow shape.
local MAXIMUM_ALPHA = 200 ---@type integer
--The maximum opacity of the shadow image (0-255).
local SHADOW_ATTENUATION = 0.05 ---@type number
--How quickly a shadow becomes weakened as an object moves upwards. The shadow will fade completely at Z = shadowSize/SHADOW_ATTENUATION.
--===========================================================================================================================================================
local mt = {__mode = "k"}
local shadow = setmetatable({}, mt) ---@type image[]
local currentX = setmetatable({}, mt) ---@type number[]
local currentY = setmetatable({}, mt) ---@type number[]
local currentZ = setmetatable({}, mt) ---@type number[]
local shadowOffsetX = setmetatable({}, mt) ---@type number[]
local shadowOffsetY = setmetatable({}, mt) ---@type number[]
local shadowAttenuation = setmetatable({}, mt) ---@type number[]
local currentAlpha = setmetatable({}, mt) ---@type integer[]
local currentWidth = setmetatable({}, mt) ---@type number[]
local currentHeight = setmetatable({}, mt) ---@type number[]
local zenithOffsetX = 1/math.tan(bj_DEGTORAD*SUN_ZENITH_ANGLE)*math.cos(bj_DEGTORAD*SUN_AZIMUTH_ANGLE)
local zenithOffsetY = 1/math.tan(bj_DEGTORAD*SUN_ZENITH_ANGLE)*math.sin(bj_DEGTORAD*SUN_AZIMUTH_ANGLE)
local GetLocZ = nil ---@type function
local moveableLoc = nil ---@type location
UNIT_SHADOW_PATH = "ReplaceableTextures\\Shadows\\Shadow.blp"
FLYER_SHADOW_PATH = "ReplaceableTextures\\Shadows\\ShadowFlyer.blp"
---Creates a special effect and adds a shadow. shadowWidth/shadowHeight is the size at scale 1. zOffset is the z-coordinate at which the shadow-casting effect is considered on the ground. This value is used to determine the shadow position dependent on the sun's zenith angle.
---@param modelPath string
---@param x number
---@param y number
---@param shadowPath string
---@param shadowWidth number
---@param shadowHeight number
---@param xOffset? number
---@param yOffset? number
---@return effect
function AddShadowedEffect(modelPath, x, y, shadowPath, shadowWidth, shadowHeight, xOffset, yOffset)
local effect = AddSpecialEffect(modelPath, x, y)
shadow[effect] = CreateImage(shadowPath, shadowWidth, shadowHeight, 0, x + (xOffset or 0) - 0.5*shadowWidth, y + (yOffset or 0) - 0.5*shadowHeight, 0, 0, 0, 0, 1)
SetImageRenderAlways(shadow[effect], true)
SetImageColor(shadow[effect], 255, 255, 255, MAXIMUM_ALPHA)
SetImageAboveWater(shadow[effect], false, true)
currentWidth[effect] = shadowWidth
currentHeight[effect] = shadowHeight
shadowOffsetX[effect] = xOffset or 0
shadowOffsetY[effect] = yOffset or 0
shadowAttenuation[effect] = SHADOW_ATTENUATION/math.max(shadowHeight, shadowWidth)
currentAlpha[effect] = MAXIMUM_ALPHA
currentX[effect], currentY[effect] = x, y
currentZ[effect] = GetLocZ(x, y)
return effect
end
---@param whichEffect effect
function DestroyShadowedEffect(whichEffect)
DestroyEffect(whichEffect)
DestroyImage(shadow[whichEffect])
end
---@param whichEffect effect
---@param x number
---@param y number
---@param z number
function SetShadowedEffectPosition(whichEffect, x, y, z)
BlzSetSpecialEffectPosition(whichEffect, x, y, z)
currentX[whichEffect], currentY[whichEffect], currentZ[whichEffect] = x, y, z
local terrainZ = GetLocZ(x, y)
local dz = (z - terrainZ)
local alpha = (currentAlpha[whichEffect]*(1 - (shadowAttenuation[whichEffect]*dz))) // 1
if alpha < 0 then
alpha = 0
end
SetImageColor(shadow[whichEffect], 255, 255, 255, alpha)
x = x + shadowOffsetX[whichEffect] + zenithOffsetX*dz
y = y + shadowOffsetY[whichEffect] + zenithOffsetY*dz
SetImagePosition(shadow[whichEffect], x + shadowOffsetX[whichEffect] - 0.5*currentWidth[whichEffect], y + shadowOffsetY[whichEffect] - 0.5*currentHeight[whichEffect], 0)
end
---@param whichEffect effect
---@param x number
function SetShadowedEffectX(whichEffect, x)
SetShadowedEffectPosition(whichEffect, x, currentY[whichEffect], currentZ[whichEffect])
end
---@param whichEffect effect
---@param y number
function SetShadowedEffectY(whichEffect, y)
SetShadowedEffectPosition(whichEffect, currentX[whichEffect], y, currentZ[whichEffect])
end
---@param whichEffect effect
---@param z number
function SetShadowedEffectZ(whichEffect, z)
SetShadowedEffectPosition(whichEffect, currentX[whichEffect], currentY[whichEffect], z)
end
---@param whichEffect effect
---@param alpha integer
function SetShadowedEffectAlpha(whichEffect, alpha)
local x = currentX[whichEffect]
local y = currentY[whichEffect]
local z = currentZ[whichEffect]
local terrainZ = GetLocZ(x, y)
currentAlpha[whichEffect] = alpha
BlzSetSpecialEffectAlpha(whichEffect, alpha)
alpha = (currentAlpha[whichEffect]*(1 - (shadowAttenuation[whichEffect]*(z - terrainZ)))) // 1
if alpha < 0 then
alpha = 0
end
SetImageColor(shadow[whichEffect], 255, 255, 255, alpha)
end
OnInit.final(function()
local precomputedHeightMap = Require.optionally "PrecomputedHeightMap"
if precomputedHeightMap then
GetLocZ = _G.GetTerrainZ
else
moveableLoc = Location(0, 0)
GetLocZ = function(x, y)
MoveLocation(moveableLoc, x, y)
return GetLocationZ(moveableLoc)
end
end
end)
end
Lua:
if Debug then Debug.beginFile "SpecialEffectShadows" end
do
--[[
=============================================================================================================================================================
Special Effect Shadows (alternate version)
by Antares
Requires:
PrecomputedHeightMap (optional) https://www.hiveworkshop.com/threads/precomputed-synchronized-terrain-height-map.353477/
TotalInitialization https://www.hiveworkshop.com/threads/total-initialization.317099/
Hook https://www.hiveworkshop.com/threads/hook.339153/
=============================================================================================================================================================
Allows the creation of objects represented by special effects that cast shadows. Shadows are represented by images. This version uses Hooks to modify the
BlzSetSpecialEffect natives to also affect the attached shadow, if it exists.
To add a shadow to an effect, use AddShadowToEffect. You need to know the coordinates of the special effect for the shadow to be created at the right position.
However, even if you don't know the location, any update of its location with BlzSetSpecialEffectPosition will update the shadow automatically.
The AddShadowToEffect function requires a path for the shadow texture. There are two preset constants: UNIT_SHADOW_PATH is the standard shadow that ground
units use. FLYER_SHADOW_PATH is the shadow that flying units use. Building shadows have a weird format and cannot be used without converting them first.
=============================================================================================================================================================
Functions
=============================================================================================================================================================
AddShadowToEffect(whichEffect, x, y, shadowPath, shadowWidth, shadowHeight, xOffset, yOffset)
=============================================================================================================================================================
Config
=============================================================================================================================================================
]]
local SUN_ZENITH_ANGLE = 45 ---@type number
--Determines the direction of the sun light in degrees. 90 = sun at the zenith. Does not affect shadow shape.
local SUN_AZIMUTH_ANGLE = 45 ---@type number
--Determines the direction of the sun light in degrees. 0 = shadows cast in positive x-direction. Does not affect shadow shape.
local MAXIMUM_ALPHA = 200 ---@type integer
--The maximum opacity of the shadow image (0-255).
local SHADOW_ATTENUATION = 0.05 ---@type number
--How quickly a shadow becomes weakened as an object moves upwards. The shadow will fade completely at Z = shadowSize/SHADOW_ATTENUATION.
--===========================================================================================================================================================
local mt = {__mode = "k"}
local shadow = setmetatable({}, mt) ---@type image[]
local currentX = setmetatable({}, mt) ---@type number[]
local currentY = setmetatable({}, mt) ---@type number[]
local currentZ = setmetatable({}, mt) ---@type number[]
local shadowOffsetX = setmetatable({}, mt) ---@type number[]
local shadowOffsetY = setmetatable({}, mt) ---@type number[]
local shadowAttenuation = setmetatable({}, mt) ---@type number[]
local currentAlpha = setmetatable({}, mt) ---@type integer[]
local currentWidth = setmetatable({}, mt) ---@type number[]
local currentHeight = setmetatable({}, mt) ---@type number[]
local zenithOffsetX = 1/math.tan(bj_DEGTORAD*SUN_ZENITH_ANGLE)*math.cos(bj_DEGTORAD*SUN_AZIMUTH_ANGLE)
local zenithOffsetY = 1/math.tan(bj_DEGTORAD*SUN_ZENITH_ANGLE)*math.sin(bj_DEGTORAD*SUN_AZIMUTH_ANGLE)
local GetLocZ = nil ---@type function
local moveableLoc = nil ---@type location
UNIT_SHADOW_PATH = "ReplaceableTextures\\Shadows\\Shadow.blp"
FLYER_SHADOW_PATH = "ReplaceableTextures\\Shadows\\ShadowFlyer.blp"
---Add a shadow to an existing special effect. shadowWidth/shadowHeight is the size at scale 1. zOffset is the z-coordinate at which the shadow-casting effect is considered on the ground. This value is used to determine the shadow position dependent on the sun's zenith angle.
---@param whichEffect effect
---@param x number
---@param y number
---@param shadowPath string
---@param shadowWidth number
---@param shadowHeight number
---@param xOffset? number
---@param yOffset? number
function AddShadowToEffect(whichEffect, x, y, shadowPath, shadowWidth, shadowHeight, xOffset, yOffset)
shadow[whichEffect] = CreateImage(shadowPath, shadowWidth, shadowHeight, 0, x + (xOffset or 0) - 0.5*shadowWidth, y + (yOffset or 0) - 0.5*shadowHeight, 0, 0, 0, 0, 1)
SetImageRenderAlways(shadow[whichEffect], true)
SetImageColor(shadow[whichEffect], 255, 255, 255, MAXIMUM_ALPHA)
SetImageAboveWater(shadow[whichEffect], false, true)
currentWidth[whichEffect] = shadowWidth
currentHeight[whichEffect] = shadowHeight
shadowOffsetX[whichEffect] = xOffset or 0
shadowOffsetY[whichEffect] = yOffset or 0
shadowAttenuation[whichEffect] = SHADOW_ATTENUATION/math.max(shadowHeight, shadowWidth)
currentAlpha[whichEffect] = MAXIMUM_ALPHA
currentX[whichEffect], currentY[whichEffect] = x, y
currentZ[whichEffect] = GetLocZ(x, y)
end
---@param whichEffect effect
function Hook:DestroyEffect(whichEffect)
if shadow[whichEffect] then
DestroyImage(shadow[whichEffect])
end
self.old(whichEffect)
end
---@param whichEffect effect
---@param x number
---@param y number
---@param z number
function Hook:BlzSetSpecialEffectPosition(whichEffect, x, y, z)
self.old(whichEffect, x, y, z)
if shadow[whichEffect] then
currentX[whichEffect], currentY[whichEffect], currentZ[whichEffect] = x, y, z
local terrainZ = GetLocZ(x, y)
local dz = (z - terrainZ)
local alpha = (currentAlpha[whichEffect]*(1 - (shadowAttenuation[whichEffect]*dz))) // 1
if alpha < 0 then
alpha = 0
end
SetImageColor(shadow[whichEffect], 255, 255, 255, alpha)
x = x + shadowOffsetX[whichEffect] + zenithOffsetX*dz
y = y + shadowOffsetY[whichEffect] + zenithOffsetY*dz
SetImagePosition(shadow[whichEffect], x + shadowOffsetX[whichEffect] - 0.5*currentWidth[whichEffect], y + shadowOffsetY[whichEffect] - 0.5*currentHeight[whichEffect], 0)
end
end
---@param whichEffect effect
---@param x number
function Hook:BlzSetSpecialEffectX(whichEffect, x)
if shadow[whichEffect] then
BlzSetSpecialEffectPosition(whichEffect, x, currentY[whichEffect], currentZ[whichEffect])
else
self.old(whichEffect, x)
end
end
---@param whichEffect effect
---@param y number
function Hook:BlzSetSpecialEffectY(whichEffect, y)
if shadow[whichEffect] then
BlzSetSpecialEffectPosition(whichEffect, currentX[whichEffect], y, currentZ[whichEffect])
else
self.old(whichEffect, y)
end
end
---@param whichEffect effect
---@param z number
function Hook:BlzSetSpecialEffectZ(whichEffect, z)
if shadow[whichEffect] then
BlzSetSpecialEffectPosition(whichEffect, currentX[whichEffect], currentY[whichEffect], z)
else
self.old(whichEffect, z)
end
end
---@param whichEffect effect
---@param alpha integer
function Hook:BlzSetSpecialEffectAlpha(whichEffect, alpha)
BlzSetSpecialEffectAlpha(whichEffect, alpha)
if shadow[whichEffect] then
local x = currentX[whichEffect]
local y = currentY[whichEffect]
local z = currentZ[whichEffect]
local terrainZ = GetLocZ(x, y)
currentAlpha[whichEffect] = alpha
alpha = (currentAlpha[whichEffect]*(1 - (shadowAttenuation[whichEffect]*(z - terrainZ)))) // 1
if alpha < 0 then
alpha = 0
end
SetImageColor(shadow[whichEffect], 255, 255, 255, alpha)
end
end
OnInit.final(function()
local precomputedHeightMap = Require.optionally "PrecomputedHeightMap"
if precomputedHeightMap then
GetLocZ = _G.GetTerrainZ
else
moveableLoc = Location(0, 0)
GetLocZ = function(x, y)
MoveLocation(moveableLoc, x, y)
return GetLocationZ(moveableLoc)
end
end
end)
endContents
Reviews
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
It might be, I'd have to do some tests. If you're using this for missiles, it's certainly not necessary to adjust Pitch/Roll/Alpha of the shadow every step, which would improve performance. The version I'll have for my engine will do this.
But the main reason I prefer special effects is that they are more versatile (Yaw, Pitch, Roll, asynchronous positions) and are much easier to deal with.
- Joined
- Jan 1, 2011
- Messages
- 1,534
Have you considered images instead of a model? It should work seamlessly with the terrain
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
It would probably work better. I just have to work-around the issue that you can't stretch an image in diagonal direction.
Spell Reviewer
- Joined
- Nov 18, 2012
- Messages
- 2,010
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And - All (Conditions) are true
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Conditions
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Or - Any (Conditions) are true
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Conditions
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((Picked player) controller) Equal to User
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((Picked player) controller) Equal to Computer
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((Picked player) controller) Not equal to None
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((Picked player) slot status) Equal to Is playing
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-
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If - Conditions
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((Picked player) controller) Equal to User
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((Picked player) controller) Not equal to Computer
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((Picked player) controller) Not equal to None
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((Picked player) slot status) Equal to Is playing
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You should use your own integer loop variables instead of Integer A and B, it's less susceptible to unexpected bugs.
Useful for tournament and minigame type of maps.
Edit: I need a dose of sleep...
Last edited:
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
I think you got the wrong guy 
.
.
Spell Reviewer
- Joined
- Nov 18, 2012
- Messages
- 2,010
Back to pending due to confusion.
I have no idea what the hell happened, must be been me needing a dose of sleep last night.I think you got the wrong guy
Spell Reviewer
- Joined
- Nov 18, 2012
- Messages
- 2,010
Seems like it's using the previous version of PrecomputedHeightMap 
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
Yea, I still need to update all of my resources using it.Seems like it's using the previous version of PrecomputedHeightMap
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
Complete revamp of this system. I found the correct shadow textures in the archive and figured out how to use the image natives, so the library no longer uses special effects to represent the shadows (sorry @Vinz 
). This has the advantage that they don't clip on jagged terrain and look janky, but the disadvantage that they can no longer be rescaled in both dimensions easily.
There are two shadow textures you can use, the ground unit shadow and the flying unit shadow. Building shadows are in a weird format and cannot be used without converting them first. The library also allows you to use your own shadow texture if you wish.
). This has the advantage that they don't clip on jagged terrain and look janky, but the disadvantage that they can no longer be rescaled in both dimensions easily.There are two shadow textures you can use, the ground unit shadow and the flying unit shadow. Building shadows are in a weird format and cannot be used without converting them first. The library also allows you to use your own shadow texture if you wish.
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
Added an alternate version using Hook.
Spell Reviewer
- Joined
- Nov 18, 2012
- Messages
- 2,010
You are missing the
Everything else looks fine, except for that you don't provide a example for the Hook version, although that's changing one line and adding another.
Useful resource for a more realistic effect, in order words, makes it easier to distinguish if an object (effect) is in the air or near/on the ground.
Approved
if Debug then Debug.endFile() end line at the end of SpecialEffectShadows, SpecialEffectShadows Hook and PrecomputedHeightMap scripts. I suspect this happens on the PrecumptedHeightMap resource too.Everything else looks fine, except for that you don't provide a example for the Hook version, although that's changing one line and adding another.
Useful resource for a more realistic effect, in order words, makes it easier to distinguish if an object (effect) is in the air or near/on the ground.
Approved
Spell Reviewer
- Joined
- Dec 13, 2009
- Messages
- 982
