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RDPipelineColorBlendStateAttachment

Inherits: RefCounted < Object

Pipeline color blend state attachment (used by RenderingDevice).

Description

Controls how blending between source and destination fragments is performed when using RenderingDevice.

For reference, this is how common user-facing blend modes are implemented in Redot's 2D renderer:

Mix:

var attachment = RDPipelineColorBlendStateAttachment.new()
attachment.enable_blend = true
attachment.color_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.src_color_blend_factor = RenderingDevice.BLEND_FACTOR_SRC_ALPHA
attachment.dst_color_blend_factor = RenderingDevice.BLEND_FACTOR_ONE_MINUS_SRC_ALPHA
attachment.alpha_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.src_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ONE
attachment.dst_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ONE_MINUS_SRC_ALPHA

Add:

var attachment = RDPipelineColorBlendStateAttachment.new()
attachment.enable_blend = true
attachment.alpha_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.color_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.src_color_blend_factor = RenderingDevice.BLEND_FACTOR_SRC_ALPHA
attachment.dst_color_blend_factor = RenderingDevice.BLEND_FACTOR_ONE
attachment.src_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_SRC_ALPHA
attachment.dst_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ONE

Subtract:

var attachment = RDPipelineColorBlendStateAttachment.new()
attachment.enable_blend = true
attachment.alpha_blend_op = RenderingDevice.BLEND_OP_REVERSE_SUBTRACT
attachment.color_blend_op = RenderingDevice.BLEND_OP_REVERSE_SUBTRACT
attachment.src_color_blend_factor = RenderingDevice.BLEND_FACTOR_SRC_ALPHA
attachment.dst_color_blend_factor = RenderingDevice.BLEND_FACTOR_ONE
attachment.src_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_SRC_ALPHA
attachment.dst_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ONE

Multiply:

var attachment = RDPipelineColorBlendStateAttachment.new()
attachment.enable_blend = true
attachment.alpha_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.color_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.src_color_blend_factor = RenderingDevice.BLEND_FACTOR_DST_COLOR
attachment.dst_color_blend_factor = RenderingDevice.BLEND_FACTOR_ZERO
attachment.src_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_DST_ALPHA
attachment.dst_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ZERO

Pre-multiplied alpha:

var attachment = RDPipelineColorBlendStateAttachment.new()
attachment.enable_blend = true
attachment.alpha_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.color_blend_op = RenderingDevice.BLEND_OP_ADD
attachment.src_color_blend_factor = RenderingDevice.BLEND_FACTOR_ONE
attachment.dst_color_blend_factor = RenderingDevice.BLEND_FACTOR_ONE_MINUS_SRC_ALPHA
attachment.src_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ONE
attachment.dst_alpha_blend_factor = RenderingDevice.BLEND_FACTOR_ONE_MINUS_SRC_ALPHA

Properties

BlendOperation	alpha_blend_op	`0`
BlendOperation	color_blend_op	`0`
BlendFactor	dst_alpha_blend_factor	`0`
BlendFactor	dst_color_blend_factor	`0`
bool	enable_blend	`false`
BlendFactor	src_alpha_blend_factor	`0`
BlendFactor	src_color_blend_factor	`0`
bool	write_a	`true`
bool	write_b	`true`
bool	write_g	`true`
bool	write_r	`true`

Methods

void	set_as_mix()

Property Descriptions

BlendOperation alpha_blend_op = 0 🔗

void set_alpha_blend_op(value: BlendOperation)
BlendOperation get_alpha_blend_op()

The blend mode to use for the alpha channel.

BlendOperation color_blend_op = 0 🔗

void set_color_blend_op(value: BlendOperation)
BlendOperation get_color_blend_op()

The blend mode to use for the red/green/blue color channels.

BlendFactor dst_alpha_blend_factor = 0 🔗

void set_dst_alpha_blend_factor(value: BlendFactor)
BlendFactor get_dst_alpha_blend_factor()

Controls how the blend factor for the alpha channel is determined based on the destination's fragments.

BlendFactor dst_color_blend_factor = 0 🔗

void set_dst_color_blend_factor(value: BlendFactor)
BlendFactor get_dst_color_blend_factor()

Controls how the blend factor for the color channels is determined based on the destination's fragments.

bool enable_blend = false 🔗

void set_enable_blend(value: bool)
bool get_enable_blend()

If true, performs blending between the source and destination according to the factors defined in src_color_blend_factor, dst_color_blend_factor, src_alpha_blend_factor and dst_alpha_blend_factor. The blend modes color_blend_op and alpha_blend_op are also taken into account, with write_r, write_g, write_b and write_a controlling the output.

BlendFactor src_alpha_blend_factor = 0 🔗

void set_src_alpha_blend_factor(value: BlendFactor)
BlendFactor get_src_alpha_blend_factor()

Controls how the blend factor for the alpha channel is determined based on the source's fragments.

BlendFactor src_color_blend_factor = 0 🔗

void set_src_color_blend_factor(value: BlendFactor)
BlendFactor get_src_color_blend_factor()

Controls how the blend factor for the color channels is determined based on the source's fragments.

bool write_a = true 🔗

void set_write_a(value: bool)
bool get_write_a()

If true, writes the new alpha channel to the final result.

bool write_b = true 🔗

void set_write_b(value: bool)
bool get_write_b()

If true, writes the new blue color channel to the final result.

bool write_g = true 🔗

void set_write_g(value: bool)
bool get_write_g()

If true, writes the new green color channel to the final result.

bool write_r = true 🔗

void set_write_r(value: bool)
bool get_write_r()

If true, writes the new red color channel to the final result.

Method Descriptions

void set_as_mix() 🔗

Convenience method to perform standard mix blending with straight (non-premultiplied) alpha. This sets enable_blend to true, src_color_blend_factor to RenderingDevice.BLEND_FACTOR_SRC_ALPHA, dst_color_blend_factor to RenderingDevice.BLEND_FACTOR_ONE_MINUS_SRC_ALPHA, src_alpha_blend_factor to RenderingDevice.BLEND_FACTOR_SRC_ALPHA and dst_alpha_blend_factor to RenderingDevice.BLEND_FACTOR_ONE_MINUS_SRC_ALPHA.