Difference between revisions of "love.graphics.newPixelEffect"

(Better (?) explanation of the effect code)
(Note placement of origin)
 
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{{newin|[[0.8.0]]|080|type=function}}
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{{newinoldin|[[0.8.0]]|080|[[0.9.0]]|090|type=function|text=It has been renamed to [[love.graphics.newShader]]}}
 
Creates a new PixelEffect object for hardware-accelerated pixel level effects.
 
Creates a new PixelEffect object for hardware-accelerated pixel level effects.
  
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== Effect Language ==
 
== Effect Language ==
Pixel effects are not programmed in Lua, but by using a special effect language instead. The effect language is basically [[http://www.opengl.org/sdk/docs/manglsl/|GLSL 1.20]] ([[http://www.opengl.org/registry/doc/GLSLangSpec.Full.1.20.8.pdf|specs]]) with a few things renamed:
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Pixel effects are not programmed in Lua, but by using a special effect language instead. The effect language is basically [http://www.opengl.org/sdk/docs/manglsl/ GLSL 1.20] ([http://www.opengl.org/registry/doc/GLSLangSpec.Full.1.20.8.pdf specs]) with a few aliases added for existing types:
  
{|
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{|cellpadding="5"
!GLSL
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!GLSL               || Effect language
!Effect language
 
 
|-
 
|-
|float
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|float             || number
|number
 
 
|-
 
|-
|sampler2D
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|sampler2D         || Image
|Image
 
 
|-
 
|-
|uniform
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|uniform           || extern
|extern
 
 
|-
 
|-
|texture2D(sampler2D tex, vec2 st)
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|texture2D(tex, uv) || Texel(tex, uv)
|Texel(Image tex, vec2 st)
 
 
|}
 
|}
  
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{{param|vec4|color|The drawing color set with [[love.graphics.setColor]].}}
 
{{param|vec4|color|The drawing color set with [[love.graphics.setColor]].}}
 
{{param|Image|texture|The texture of the image or canvas being drawn.}}
 
{{param|Image|texture|The texture of the image or canvas being drawn.}}
{{param|vec2|texture_coords|Coordinates of the pixel relative to the texture.}}
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{{param|vec2|texture_coords|Coordinates of the pixel relative to the texture. The y-axis of canvases are inverted. Coordinates (1,1) would be the top right corner of the canvas.}}
{{param|vec2|screen_coords|Coordinates of the pixel on the screen.}}
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{{param|vec2|screen_coords|Coordinates of the pixel on the screen. Pixel coordinates are not normalized (unlike texture coordinates). (0.5, 0.5) is the bottom left of the screen.}}
 
=== Returns ===
 
=== Returns ===
 
{{param|vec4|output_color|The color of the pixel.}}
 
{{param|vec4|output_color|The color of the pixel.}}
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* [[love.graphics.setPixelEffect]]
 
* [[love.graphics.setPixelEffect]]
 
[[Category:Functions]]
 
[[Category:Functions]]
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[[Sub-Category::Object Creation| ]]
 
{{#set:Description=Creates a new [[PixelEffect]].}}
 
{{#set:Description=Creates a new [[PixelEffect]].}}
 
== Other Languages ==
 
== Other Languages ==
 
{{i18n|love.graphics.newPixelEffect}}
 
{{i18n|love.graphics.newPixelEffect}}

Latest revision as of 21:50, 27 October 2016

Available since LÖVE 0.8.0 and removed in LÖVE 0.9.0
It has been renamed to love.graphics.newShader.

Creates a new PixelEffect object for hardware-accelerated pixel level effects.

A PixelEffect contains at least one function, named effect, which is the effect itself, but it can contain additional functions.

Function

Synopsis

pixeleffect = love.graphics.newPixelEffect( code )

Arguments

string code
The pixel effect code.

Returns

PixelEffect pixeleffect
A PixelEffect object for use in drawing operations.

Effect Language

Pixel effects are not programmed in Lua, but by using a special effect language instead. The effect language is basically GLSL 1.20 (specs) with a few aliases added for existing types:

GLSL Effect language
float number
sampler2D Image
uniform extern
texture2D(tex, uv) Texel(tex, uv)

Effect Function

Synopsis

vec4 effect( vec4 color, Image texture, vec2 texture_coords, vec2 screen_coords )

Arguments

vec4 color
The drawing color set with love.graphics.setColor.
Image texture
The texture of the image or canvas being drawn.
vec2 texture_coords
Coordinates of the pixel relative to the texture. The y-axis of canvases are inverted. Coordinates (1,1) would be the top right corner of the canvas.
vec2 screen_coords
Coordinates of the pixel on the screen. Pixel coordinates are not normalized (unlike texture coordinates). (0.5, 0.5) is the bottom left of the screen.

Returns

vec4 output_color
The color of the pixel.


See Also


Other Languages