Canvas (Nederlands)

Available since LÖVE 0.8.0
Het is hernoemd van Framebuffer.

Een canvas wordt gebruikt voor off-screen rendering. Denk eraan als een onzichtbaar scherm waar je op kunt tekenen, maar dat pas zichtbaar wordt wanneer je het op het daadwerkelijk zichtbare scherm tekent. Het staat ook bekend als "render to texture".

Door dingen die niet vaak van positie veranderen (zoals achtergrondelementen) naar het Canvas te tekenen en vervolgens het hele Canvas in plaats van elk item te tekenen, kun je het aantal tekenoperaties verminderen dat elke frame wordt uitgevoerd.

In versies vóór 0.10.0 konden niet alle grafische kaarten die door LÖVE werden ondersteund Canvassen gebruiken. love.graphics.isSupported("canvas") kon worden gebruikt om tijdens runtime te controleren of ondersteuning aanwezig was.


O.png Bij het tekenen van inhoud op een Canvas met reguliere alpha blending, worden de alpha-waarden van de inhoud vermenigvuldigd met de RGB-waarden ervan.

Daarom zullen de pixelkleuren van het Canvas vooraf vermenigvuldigde alpha hebben zodra het is getekend, dus bij het tekenen van het Canvas op het scherm of op een ander Canvas, moet je gebruik maken van vooraf vermenigvuldigde alpha blending – love.graphics.setBlendMode("alpha", "premultiplied").

 


Constructors

love.graphics.newCanvas Creates a new Canvas. Added since 0.8.0

Functions

Canvas:clear (Nederlands) Clears the contents of a Canvas to a specific color. Added since 0.8.0 Removed in 0.10.0
Object:release Immediately destroys the object's Lua reference. Added since 11.0
Object:type Gets the type of the object as a string.
Object:typeOf Checks whether an object is of a certain type.
Texture:getDPIScale Gets the DPI scale factor of the Texture. Added since 11.0
Texture:getDepth Gets the depth of a Volume Texture. Added since 11.0
Texture:getDepthSampleMode Gets the comparison mode used when sampling from a depth texture in a shader. Added since 11.0
Texture:getDimensions Gets the width and height of the Texture. Added since 0.9.0
Texture:getFilter Gets the filter mode of the Texture.
Texture:getFormat Gets the pixel format of the Texture. Added since 11.0
Texture:getHeight Gets the height of the Texture.
Texture:getLayerCount Gets the number of layers / slices in an Array Texture. Added since 11.0
Texture:getMipmapCount Gets the number of mipmaps contained in the Texture. Added since 11.0
Texture:getMipmapFilter Gets the mipmap filter mode for a Texture. Added since 0.9.0
Texture:getPixelDimensions Gets the width and height in pixels of the Texture. Added since 11.0
Texture:getPixelHeight Gets the height in pixels of the Texture. Added since 11.0
Texture:getPixelWidth Gets the width in pixels of the Texture. Added since 11.0
Texture:getTextureType Gets the type of the Texture. Added since 11.0
Texture:getWidth Gets the width of the Texture.
Texture:getWrap Gets the wrapping properties of a Texture.
Texture:isReadable Gets whether the Texture can be drawn and sent to a Shader. Added since 11.0
Texture:setDepthSampleMode Sets the comparison mode used when sampling from a depth texture in a shader. Added since 11.0
Texture:setFilter Sets the filter mode of the Texture.
Texture:setMipmapFilter Sets the mipmap filter mode for a Texture. Added since 0.9.0
Texture:setWrap Sets the wrapping properties of a Texture.

Enums

MipmapMode Controls whether a Canvas has mipmaps, and its behaviour when it does. Added since 11.0

Supertypes

Examples

Drawing something to the Canvas and then draw the Canvas to the screen

function love.load()
    canvas = love.graphics.newCanvas(800, 600)

    -- Rectangle is drawn to the canvas with the regular/default alpha blend mode ("alphamultiply").
    love.graphics.setCanvas(canvas)
        love.graphics.clear(0, 0, 0, 0)
        love.graphics.setBlendMode("alpha")
        love.graphics.setColor(1, 0, 0, .5)
        love.graphics.rectangle("fill", 0,0, 100,100)
    love.graphics.setCanvas()
end

function love.draw()
    -- The colors for the rectangle on the canvas have already been alpha blended.
    -- Use the "premultiplied" alpha blend mode when drawing the canvas to the screen for proper color blending.
    -- (Also set the color to white so the canvas itself doesn't get tinted.)
    love.graphics.setBlendMode("alpha", "premultiplied")
    love.graphics.setColor(1, 1, 1, 1)
    love.graphics.draw(canvas, 0,0)
    -- Observe the difference if the canvas is drawn with the regular alpha blend mode instead.
    love.graphics.setBlendMode("alpha")
    love.graphics.draw(canvas, 100,0)

    -- Rectangle is drawn directly to the screen with the regular alpha blend mode.
    love.graphics.setBlendMode("alpha")
    love.graphics.setColor(1, 0, 0, .5)
    love.graphics.rectangle("fill", 200,0, 100,100)

    -- (Helper texts.)
    love.graphics.setColor(1, 1, 1, 1)
    love.graphics.printf("canvas", 0,0, 100)
    love.graphics.printf("incorrect\n(looks too dark)", 100,0, 100)
    love.graphics.printf("rectangle\n(what canvas should look like)", 200,0, 100)
end

Save canvas as picture

	canvas:newImageData():encode("png","filename.png")

See Also


Other Languages