DxSetBlendMode: Difference between revisions

Latest revision as of 17:00, 7 November 2024

This function sets the current blend mode for the dxDraw functions. Changing the blend mode can increase the quality when drawing text or certain other images to a render target. As a general guide use modulate_add when drawing text to a render target, and add when drawing the render target to the screen. Don't forget to restore the default blend at the end - See the example below.

Syntax

bool dxSetBlendMode ( string blendMode )

Required Arguments

blendMode : The blend mode to use which can be one of:
- blend: The source textures are alpha blended to the screen/render target. This is the default mode for drawing and gives the results we all know and love.
- add: The source textures are added to the screen/render target.
- modulate_add: The source textures are multiplied by the alpha and then added to the screen/render target.
- overwrite : The source textures are overwritten. This can be useful for clearing render targets.

Returns

Returns true if successful, or false if invalid arguments were passed to the function.

Example

Click to collapse [-]

Client

This example shows how to use modulate_add and add to avoid quality problems when using a render target:

local myRenderTarget = dxCreateRenderTarget(500, 500, true)

--
-- Function to draw text to our render target texture when the 'r' key is pressed
--
function updateRenderTarget()
    dxSetRenderTarget(myRenderTarget, true)
    dxSetBlendMode("modulate_add")  -- Set 'modulate_add' when drawing stuff on the render target

    dxDrawText("Testing "..getTickCount(), 0, 0, 0, 0, tocolor(255, 255, 255, 255), 2, "clear")

    dxSetBlendMode("blend")         -- Restore default blending
    dxSetRenderTarget()             -- Restore default render target
end
bindKey("r", "down", updateRenderTarget )

--
-- Display render target contents
--
addEventHandler("onClientRender", root,
    function()
        dxSetBlendMode("add")       -- Set 'add' when drawing the render target on the screen
        dxDrawImage(100, 200, 500, 500, myRenderTarget, -10)
        dxSetBlendMode("blend")     -- Restore default blending
    end
)

Changelog

Version	Description

1.3.0-9.04425

Added overwrite

@@ Line 1: / Line 1: @@
 {{Client function}}
 __NOTOC__
-This function sets the current blend mode for the dxDraw functions. Changing the blend mode can increase the quality when drawing text or certain other images to a render target. As a general guide use '''modulate_add''' when drawing text to a render target, and '''add''' when drawing the render target to the screen. Don't forget to restore the default '''blend''' at the end.
+This function sets the current blend mode for the dxDraw functions. Changing the blend mode can increase the quality when drawing text or certain other images to a render target. As a general guide use '''modulate_add''' when drawing text to a render target, and '''add''' when drawing the render target to the screen. Don't forget to restore the default '''blend''' at the end - See the example below.
 ==Syntax==
 <syntaxhighlight lang="lua">
-bool dxSetBlendMode( string blendMode )
+bool dxSetBlendMode ( string blendMode )
 </syntaxhighlight>
 ===Required Arguments===
 *'''blendMode :''' The blend mode to use which can be one of:
-**'''blend:''' The source textures are alpha blended to the screen/render target. The is the default mode for drawing and gives the results we all know and love.
+**'''blend:''' The source textures are alpha blended to the screen/render target. This is the default mode for drawing and gives the results we all know and love.
 **'''add:''' The source textures are added to the screen/render target.
 **'''modulate_add:''' The source textures are multiplied by the alpha and then added to the screen/render target.
+**'''overwrite :''' The source textures are overwritten. This can be useful for clearing render targets.
 ==Returns==
 Returns true if successful, or ''false'' if invalid arguments were passed to the function.
 ==Example==
+<section name="Client" class="client" show="true">
+This example shows how to use '''modulate_add''' and '''add''' to avoid quality problems when using a render target:
 <syntaxhighlight lang="lua">
-TODO
+local myRenderTarget = dxCreateRenderTarget(500, 500, true)
+--
+-- Function to draw text to our render target texture when the 'r' key is pressed
+--
+function updateRenderTarget()
+    dxSetRenderTarget(myRenderTarget, true)
+    dxSetBlendMode("modulate_add")  -- Set 'modulate_add' when drawing stuff on the render target
+    dxDrawText("Testing "..getTickCount(), 0, 0, 0, 0, tocolor(255, 255, 255, 255), 2, "clear")
+    dxSetBlendMode("blend")         -- Restore default blending
+    dxSetRenderTarget()             -- Restore default render target
+end
+bindKey("r", "down", updateRenderTarget )
+--
+-- Display render target contents
+--
+addEventHandler("onClientRender", root,
+    function()
+        dxSetBlendMode("add")       -- Set 'add' when drawing the render target on the screen
+        dxDrawImage(100, 200, 500, 500, myRenderTarget, -10)
+        dxSetBlendMode("blend")     -- Restore default blending
+    end
+)
 </syntaxhighlight>
+</section>
-==Requirements==
+==Changelog==
-{{Requirements|n/a|1.3.0-9.03782|}}
+{{ChangelogHeader}}
+{{ChangelogItem|1.3.0-9.04425|Added overwrite }}
 ==See Also==
 {{Drawing_functions}}
+[[hu:dxSetBlendMode]]