Difference between revisions of "Sprite:setStencilOperation"

(mostly formatting :-) and removed language)
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__NOTOC__
 
__NOTOC__
 +
'''Available since:''' Gideros 2017.6<br/>
 +
'''Class:''' [[Sprite]]<br/>
  
<languages />
+
=== Description ===
 
 
'''<translate>Available since</translate>:''' Gideros 2017.6
 
<br/>
 
 
 
'''<translate>Class</translate>:''' [[Special:MyLanguage/Sprite|Sprite]]
 
<br/>
 
 
 
=== <translate>Description</translate> ===
 
<translate>
 
 
Allows to set a stencil operation to be used when drawing this sprite.
 
Allows to set a stencil operation to be used when drawing this sprite.
<br/>
 
    The table can contain the following fields:
 
    <ul>
 
    <li><b>stencilClear</b>: (boolean) whether the stencil should be cleared beforehand.</li>
 
    <li><b>stencilMask</b>: (integer) the mask value used in stencil operations.</li>
 
    <li><b>stencilWriteMask</b>: (integer) the mask value used when writing to stencil.</li>
 
    <li><b>stencilRef</b>: (integer) the reference value used in stencil operations.</li>
 
    <li><b>stencilFunc</b>: (integer) the stencil function to use.</li>
 
    <li><b>stencilFail</b>: (integer) the stencil operation when stencil test failed.</li>
 
    <li><b>depthFail</b>: (integer) the stencil operation when depth test failed.</li>
 
    <li><b>depthPass</b>: (integer) the stencil operation when depth test has passed.</li>
 
    </ul>
 
<br />
 
Stencil function and operations code are defined in Sprite.STENCIL_xxx fields and correspond to the GL_xxx relevant values in OpenGL stencil documentation.
 
</translate>
 
 
 
<source lang="lua">
 
<source lang="lua">
 
Sprite:setStencilOperation(op)
 
Sprite:setStencilOperation(op)
 
</source>
 
</source>
  
=== <translate>Parameters</translate> ===
 
'''op''': (table) <translate>A table containing the stencil operation settings, or nil to disable stencil</translate>
 
  
=== <translate>Examples</translate> ===
+
The '''op''' table can contain the following fields:
'''Example''':
+
*'''stencilClear''': (boolean) whether the stencil should be cleared beforehand
 +
*'''stencilMask''': (integer) the mask value used in stencil operations
 +
*'''stencilWriteMask''': (integer) the mask value used when writing to stencil
 +
*'''stencilRef''': (integer) the reference value used in stencil operations
 +
*'''stencilFunc''': (integer) the stencil function to use
 +
*'''stencilFail''': (integer) the stencil operation when stencil test failed
 +
*'''depthFail''': (integer) the stencil operation when depth test failed
 +
*'''depthPass''': (integer) the stencil operation when depth test has passed
 +
 
 +
Stencil function and operations code are defined in Sprite.STENCIL_xxx fields and correspond to the GL_xxx relevant values in OpenGL stencil documentation https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/glStencilFunc.xhtml.
 +
 
 +
=== Parameters ===
 +
'''op''': (table) a table containing the stencil operation settings, or nil to disable stencil
  
 +
=== Example ===
 +
'''A glowing ticket effect''':
 
<source lang="lua">
 
<source lang="lua">
 
-- STENCILOPERATION @hgy29
 
-- STENCILOPERATION @hgy29
Line 78: Line 67:
 
end)
 
end)
 
</source>
 
</source>
<br/>
 
  
 
{{Sprite}}
 
{{Sprite}}

Revision as of 00:36, 3 February 2021

Available since: Gideros 2017.6
Class: Sprite

Description

Allows to set a stencil operation to be used when drawing this sprite.

Sprite:setStencilOperation(op)


The op table can contain the following fields:

  • stencilClear: (boolean) whether the stencil should be cleared beforehand
  • stencilMask: (integer) the mask value used in stencil operations
  • stencilWriteMask: (integer) the mask value used when writing to stencil
  • stencilRef: (integer) the reference value used in stencil operations
  • stencilFunc: (integer) the stencil function to use
  • stencilFail: (integer) the stencil operation when stencil test failed
  • depthFail: (integer) the stencil operation when depth test failed
  • depthPass: (integer) the stencil operation when depth test has passed

Stencil function and operations code are defined in Sprite.STENCIL_xxx fields and correspond to the GL_xxx relevant values in OpenGL stencil documentation https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/glStencilFunc.xhtml.

Parameters

op: (table) a table containing the stencil operation settings, or nil to disable stencil

Example

A glowing ticket effect:

-- STENCILOPERATION @hgy29
local bg = Bitmap.new(Texture.new("gfx/vip/background.png"))
local ticket = Bitmap.new(Texture.new("gfx/vip/ticket.png"))
local text = Bitmap.new(Texture.new("gfx/vip/text.png"))
local fx1 = Bitmap.new(Texture.new("gfx/vip/fx1.png"))
local fx2 = Bitmap.new(Texture.new("gfx/vip/fx2.png"))
 
stage:addChild(bg) bg:setScale(0.5)
stage:addChild(ticket) ticket:setPosition(80,20) ticket:setScale(0.5)
ticket:addChild(fx1) fx1:setX(-100)
fx1:addChild(fx2) fx2:setX(-100)
ticket:addChild(text)
 
-- Use auto layout on ticket to center text automatically
ticket:setLayoutParameters{ rowWeights = {1}, columnWeights = {1} }
text:setLayoutConstraints{}

-- Use stencil for masking glow:
-- 1) Clear stencil and set it to '1' for every pixel drawn on 'ticket'
ticket:setStencilOperation{
	stencilClear = true, stenciMask = 1, stencilWriteMask = 1, stencilRef = 1,
	stencilFunc = Sprite.STENCIL_ALWAYS, depthPass = Sprite.STENCIL_REPLACE
}
--2) Only draw fx1/fx2 if stencil isn't 0
fx1:setStencilOperation{
	stencilClear = false, stencilMask = 1, stencilRef = 0,
	stencilFunc = Sprite.STENCIL_NOTEQUAL
}
 
local dir = 1
stage:addEventListener(Event.ENTER_FRAME, function()
	if fx1:getX() > 450 then
		dir = -1
	elseif fx1:getX() < -100 then
		dir = 1
	end
	fx1:setX(fx1:getX() + dir*5)
end)