mirror of
https://github.com/brl/mutter.git
synced 2024-11-24 00:50:42 -05:00
775 lines
26 KiB
C
775 lines
26 KiB
C
/*
|
|
* Cogl
|
|
*
|
|
* An object oriented GL/GLES Abstraction/Utility Layer
|
|
*
|
|
* Copyright (C) 2007,2008,2009 Intel Corporation.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the
|
|
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
* Boston, MA 02111-1307, USA.
|
|
*/
|
|
|
|
#if !defined(__COGL_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
|
|
#error "Only <cogl/cogl.h> can be included directly."
|
|
#endif
|
|
|
|
#ifndef __COGL_MATERIAL_H__
|
|
#define __COGL_MATERIAL_H__
|
|
|
|
G_BEGIN_DECLS
|
|
|
|
#include <cogl/cogl-types.h>
|
|
#include <cogl/cogl-matrix.h>
|
|
|
|
/**
|
|
* SECTION:cogl-material
|
|
* @short_description: Fuctions for creating and manipulating materials
|
|
*
|
|
* COGL allows creating and manipulating materials used to fill in
|
|
* geometry. Materials may simply be lighting attributes (such as an
|
|
* ambient and diffuse colour) or might represent one or more textures
|
|
* blended together.
|
|
*/
|
|
|
|
/**
|
|
* CoglMaterialFilter:
|
|
* @COGL_MATERIAL_FILTER_NEAREST: Measuring in manhatten distance from the,
|
|
* current pixel center, use the nearest texture
|
|
* texel.
|
|
* @COGL_MATERIAL_FILTER_LINEAR: Use the weighted average of the 4 texels
|
|
* nearest the current pixel center.
|
|
* @COGL_MATERIAL_FILTER_NEAREST_MIPMAP_NEAREST: Select the mimap level whose
|
|
* texel size most closely matches
|
|
* the current pixel, and use the
|
|
* COGL_MATERIAL_FILTER_NEAREST
|
|
* criterion.
|
|
* @COGL_MATERIAL_FILTER_LINEAR_MIPMAP_NEAREST: Select the mimap level whose
|
|
* texel size most closely matches
|
|
* the current pixel, and use the
|
|
* COGL_MATERIAL_FILTER_LINEAR
|
|
* criterion.
|
|
* @COGL_MATERIAL_FILTER_NEAREST_MIPMAP_LINEAR: Select the two mimap levels
|
|
* whose texel size most closely
|
|
* matches the current pixel, use
|
|
* the COGL_MATERIAL_FILTER_NEAREST
|
|
* criterion on each one and take
|
|
* their weighted average.
|
|
* @COGL_MATERIAL_FILTER_LINEAR_MIPMAP_LINEAR: Select the two mimap levels
|
|
* whose texel size most closely
|
|
* matches the current pixel, use
|
|
* the COGL_MATERIAL_FILTER_LINEAR
|
|
* criterion on each one and take
|
|
* their weighted average.
|
|
*
|
|
* Texture filtering is used whenever the current pixel maps either to more
|
|
* than one texture element (texel) or less than one. These filter enums
|
|
* correspond to different strategies used to come up with a pixel color, by
|
|
* possibly referring to multiple neighbouring texels and taking a weighted
|
|
* average or simply using the nearest texel.
|
|
*/
|
|
typedef enum _CoglMaterialFilter
|
|
{
|
|
COGL_MATERIAL_FILTER_NEAREST = GL_NEAREST,
|
|
COGL_MATERIAL_FILTER_LINEAR = GL_LINEAR,
|
|
COGL_MATERIAL_FILTER_NEAREST_MIPMAP_NEAREST = GL_NEAREST_MIPMAP_NEAREST,
|
|
COGL_MATERIAL_FILTER_LINEAR_MIPMAP_NEAREST = GL_LINEAR_MIPMAP_NEAREST,
|
|
COGL_MATERIAL_FILTER_NEAREST_MIPMAP_LINEAR = GL_NEAREST_MIPMAP_LINEAR,
|
|
COGL_MATERIAL_FILTER_LINEAR_MIPMAP_LINEAR = GL_LINEAR_MIPMAP_LINEAR
|
|
} CoglMaterialFilter;
|
|
|
|
/**
|
|
* cogl_material_new:
|
|
*
|
|
* Allocates and initializes a blank white material
|
|
*
|
|
* Returns: a handle to the new material
|
|
*/
|
|
CoglHandle cogl_material_new (void);
|
|
|
|
/**
|
|
* cogl_material_ref:
|
|
* @handle: a @CoglHandle.
|
|
*
|
|
* Increment the reference count for a cogl material.
|
|
*
|
|
* Returns: the @handle.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
CoglHandle cogl_material_ref (CoglHandle handle);
|
|
|
|
/**
|
|
* cogl_material_unref:
|
|
* @handle: a @CoglHandle.
|
|
*
|
|
* Decrement the reference count for a cogl material.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_unref (CoglHandle handle);
|
|
|
|
/**
|
|
* cogl_is_material:
|
|
* @handle: A CoglHandle
|
|
*
|
|
* Gets whether the given handle references an existing material object.
|
|
*
|
|
* Returns: %TRUE if the handle references a #CoglMaterial,
|
|
* %FALSE otherwise
|
|
*/
|
|
gboolean cogl_is_material (CoglHandle handle);
|
|
|
|
/**
|
|
* cogl_material_set_color:
|
|
* @material: A CoglMaterial object
|
|
* @color: The components of the color
|
|
*
|
|
* This is the basic color of the material, used when no lighting is enabled.
|
|
*
|
|
* Note that if you don't add any layers to the material then the color
|
|
* will be blended unmodified with the destination; the default blend
|
|
* expects premultiplied colors: for example, use (0.5, 0.0, 0.0, 0.5) for
|
|
* semi-transparent red. See cogl_color_premultiply().
|
|
*
|
|
* The default value is (1.0, 1.0, 1.0, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_color (CoglHandle material, const CoglColor *color);
|
|
|
|
/**
|
|
* cogl_material_set_color4ub:
|
|
* @material: A CoglMaterial object
|
|
* @red: The red component
|
|
* @green: The green component
|
|
* @blue: The blue component
|
|
* @alpha: The alpha component
|
|
*
|
|
* This is the basic color of the material, used when no lighting is enabled.
|
|
*
|
|
* The default value is (0xff, 0xff, 0xff, 0xff)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_color4ub (CoglHandle material,
|
|
guint8 red,
|
|
guint8 green,
|
|
guint8 blue,
|
|
guint8 alpha);
|
|
|
|
/**
|
|
* cogl_material_set_color4f:
|
|
* @material: A CoglMaterial object
|
|
* @red: The red component
|
|
* @green: The green component
|
|
* @blue: The blue component
|
|
* @alpha: The alpha component
|
|
*
|
|
* This is the basic color of the material, used when no lighting is enabled.
|
|
*
|
|
* The default value is (1.0, 1.0, 1.0, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_color4f (CoglHandle material,
|
|
float red,
|
|
float green,
|
|
float blue,
|
|
float alpha);
|
|
|
|
/**
|
|
* cogl_material_get_color:
|
|
* @material: A CoglMaterial object
|
|
* @color: The location to store the color
|
|
*
|
|
* This retrieves the current material color.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_get_color (CoglHandle material, CoglColor *color);
|
|
|
|
/**
|
|
* cogl_material_set_ambient:
|
|
* @material: A CoglMaterial object
|
|
* @ambient: The components of the desired ambient color
|
|
*
|
|
* Exposing the standard OpenGL lighting model; this function sets
|
|
* the material's ambient color. The ambient color affects the overall
|
|
* color of the object. Since the diffuse color will be intense when
|
|
* the light hits the surface directly, the ambient will most aparent
|
|
* where the light hits at a slant.
|
|
*
|
|
* The default value is (0.2, 0.2, 0.2, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_ambient (CoglHandle material,
|
|
const CoglColor *ambient);
|
|
|
|
/**
|
|
* cogl_material_get_ambient:
|
|
* @material: A CoglMaterial object
|
|
* @ambient: The location to store the ambient color
|
|
*
|
|
* This retrieves the materials current ambient color.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_get_ambient (CoglHandle material, CoglColor *ambient);
|
|
|
|
/**
|
|
* cogl_material_set_diffuse:
|
|
* @material: A CoglMaterial object
|
|
* @diffuse: The components of the desired diffuse color
|
|
*
|
|
* Exposing the standard OpenGL lighting model; this function sets
|
|
* the material's diffuse color. The diffuse color is most intense
|
|
* where the light hits the surface directly; perpendicular to the
|
|
* surface.
|
|
*
|
|
* The default value is (0.8, 0.8, 0.8, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_diffuse (CoglHandle material,
|
|
const CoglColor *diffuse);
|
|
|
|
/**
|
|
* cogl_material_get_diffuse:
|
|
* @material: A CoglMaterial object
|
|
* @diffuse: The location to store the diffuse color
|
|
*
|
|
* This retrieves the materials current diffuse color.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_get_diffuse (CoglHandle material, CoglColor *diffuse);
|
|
|
|
/**
|
|
* cogl_material_set_ambient_and_diffuse:
|
|
* @material: A CoglMaterial object
|
|
* @color: The components of the desired ambient and diffuse colors
|
|
*
|
|
* This is a convenience for setting the diffuse and ambient color
|
|
* of the material at the same time.
|
|
*
|
|
* The default ambient color is (0.2, 0.2, 0.2, 1.0)
|
|
* The default diffuse color is (0.8, 0.8, 0.8, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_ambient_and_diffuse (CoglHandle material,
|
|
const CoglColor *color);
|
|
|
|
/**
|
|
* cogl_material_set_specular:
|
|
* @material: A CoglMaterial object
|
|
* @specular: The components of the desired specular color
|
|
*
|
|
* Exposing the standard OpenGL lighting model; this function sets
|
|
* the material's specular color. The intensity of the specular color
|
|
* depends on the viewport position, and is brightest along the lines
|
|
* of reflection.
|
|
*
|
|
* The default value is (0.0, 0.0, 0.0, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_specular (CoglHandle material,
|
|
const CoglColor *specular);
|
|
|
|
/**
|
|
* cogl_material_get_specular:
|
|
* @material: A CoglMaterial object
|
|
* @specular: The location to store the specular color
|
|
*
|
|
* This retrieves the materials current specular color.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_get_specular (CoglHandle material, CoglColor *specular);
|
|
|
|
/**
|
|
* cogl_material_set_shininess:
|
|
* @material: A CoglMaterial object
|
|
* @shininess: The desired shininess; range: [0.0, 1.0]
|
|
*
|
|
* This function sets the materials shininess which determines how
|
|
* specular highlights are calculated. A higher shininess will produce
|
|
* smaller brigher highlights.
|
|
*
|
|
* The default value is 0.0
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_shininess (CoglHandle material,
|
|
float shininess);
|
|
/**
|
|
* cogl_material_get_shininess:
|
|
* @material: A CoglMaterial object
|
|
*
|
|
* This retrieves the materials current emission color.
|
|
*
|
|
* Return value: The materials current shininess value
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
float cogl_material_get_shininess (CoglHandle material);
|
|
|
|
/**
|
|
* cogl_material_set_emission:
|
|
* @material: A CoglMaterial object
|
|
* @emission: The components of the desired emissive color
|
|
*
|
|
* Exposing the standard OpenGL lighting model; this function sets
|
|
* the material's emissive color. It will look like the surface is
|
|
* a light source emitting this color.
|
|
*
|
|
* The default value is (0.0, 0.0, 0.0, 1.0)
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_emission (CoglHandle material,
|
|
const CoglColor *emission);
|
|
|
|
/**
|
|
* cogl_material_get_emission:
|
|
* @material: A CoglMaterial object
|
|
* @emission: The location to store the emission color
|
|
*
|
|
* This retrieves the materials current emission color.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_get_emission (CoglHandle material, CoglColor *emission);
|
|
|
|
/**
|
|
* CoglMaterialAlphaFunc:
|
|
* @COGL_MATERIAL_ALPHA_FUNC_NEVER: Never let the fragment through.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_LESS: Let the fragment through if the incoming
|
|
* alpha value is less than the reference alpha
|
|
* value.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_EQUAL: Let the fragment through if the incoming
|
|
* alpha value equals the reference alpha
|
|
* value.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_LEQUAL: Let the fragment through if the incoming
|
|
* alpha value is less than or equal to the
|
|
* reference alpha value.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_GREATER: Let the fragment through if the incoming
|
|
* alpha value is greater than the reference
|
|
* alpha value.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_NOTEQUAL: Let the fragment through if the incoming
|
|
* alpha value does not equal the reference
|
|
* alpha value.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_GEQUAL: Let the fragment through if the incoming
|
|
* alpha value is greater than or equal to the
|
|
* reference alpha value.
|
|
* @COGL_MATERIAL_ALPHA_FUNC_ALWAYS: Always let the fragment through.
|
|
*
|
|
* Alpha testing happens before blending primitives with the framebuffer and
|
|
* gives an opportunity to discard fragments based on a comparison with the
|
|
* incoming alpha value and a reference alpha value. The #CoglMaterialAlphaFunc
|
|
* determines how the comparison is done.
|
|
*/
|
|
typedef enum _CoglMaterialAlphaFunc
|
|
{
|
|
COGL_MATERIAL_ALPHA_FUNC_NEVER = GL_NEVER,
|
|
COGL_MATERIAL_ALPHA_FUNC_LESS = GL_LESS,
|
|
COGL_MATERIAL_ALPHA_FUNC_EQUAL = GL_EQUAL,
|
|
COGL_MATERIAL_ALPHA_FUNC_LEQUAL = GL_LEQUAL,
|
|
COGL_MATERIAL_ALPHA_FUNC_GREATER = GL_GREATER,
|
|
COGL_MATERIAL_ALPHA_FUNC_NOTEQUAL = GL_NOTEQUAL,
|
|
COGL_MATERIAL_ALPHA_FUNC_GEQUAL = GL_GEQUAL,
|
|
COGL_MATERIAL_ALPHA_FUNC_ALWAYS = GL_ALWAYS
|
|
} CoglMaterialAlphaFunc;
|
|
|
|
/**
|
|
* cogl_material_set_alpha_test_function:
|
|
* @material: A CoglMaterial object
|
|
* @alpha_func: A @CoglMaterialAlphaFunc constant
|
|
* @alpha_reference: A reference point that the chosen alpha function uses
|
|
* to compare incoming fragments to.
|
|
*
|
|
* Before a primitive is blended with the framebuffer, it goes through an
|
|
* alpha test stage which lets you discard fragments based on the current
|
|
* alpha value. This function lets you change the function used to evaluate
|
|
* the alpha channel, and thus determine which fragments are discarded
|
|
* and which continue on to the blending stage.
|
|
*
|
|
* The default is COGL_MATERIAL_ALPHA_FUNC_ALWAYS
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_alpha_test_function (CoglHandle material,
|
|
CoglMaterialAlphaFunc alpha_func,
|
|
float alpha_reference);
|
|
|
|
/**
|
|
* cogl_material_set_blend:
|
|
* @material: A CoglMaterial object
|
|
* @blend_string: A <link linkend="cogl-Blend-Strings">Cogl blend string</link>
|
|
* describing the desired blend function.
|
|
* @error: A GError that may report lack of driver support if you give
|
|
* separate blend string statements for the alpha channel and RGB
|
|
* channels since some drivers or backends such as GLES 1.1 dont
|
|
* support this. May be %NULL, in which case a warning will be
|
|
* printed out if an error is encountered.
|
|
*
|
|
* If not already familiar; please refer
|
|
* <link linkend="cogl-Blend-Strings">here</link> for an overview of what blend
|
|
* strings are and there syntax.
|
|
*
|
|
* Blending occurs after the alpha test function, and combines fragments with
|
|
* the framebuffer.
|
|
|
|
* Currently the only blend function Cogl exposes is ADD(). So any valid
|
|
* blend statements will be of the form:
|
|
*
|
|
* <programlisting>
|
|
* <channel-mask>=ADD(SRC_COLOR*(<factor>), DST_COLOR*(<factor>))
|
|
* </programlisting>
|
|
*
|
|
* <warning>The brackets around blend factors are currently not optional!</warning>
|
|
*
|
|
* This is the list of source-names usable as blend factors:
|
|
* <itemizedlist>
|
|
* <listitem>SRC_COLOR: The color of the in comming fragment</listitem>
|
|
* <listitem>DST_COLOR: The color of the framebuffer</listitem>
|
|
* <listitem>
|
|
* CONSTANT: The constant set via cogl_material_set_blend_constant()</listitem>
|
|
* </itemizedlist>
|
|
* The source names can be used according to the
|
|
* <link linkend="cogl-Blend-String-syntax">color-source and factor syntax</link>,
|
|
* so for example "(1-SRC_COLOR[A])" would be a valid factor, as would
|
|
* "(CONSTANT[RGB])"
|
|
*
|
|
* These can also be used as factors:
|
|
* <itemizedlist>
|
|
* <listitem>0: (0, 0, 0, 0)</listitem>
|
|
* <listitem>1: (1, 1, 1, 1)</listitem>
|
|
* <listitem>SRC_ALPHA_SATURATE_FACTOR: (f,f,f,1)
|
|
* where f=MIN(SRC_COLOR[A],1-DST_COLOR[A])</listitem>
|
|
* </itemizedlist>
|
|
* <para>
|
|
* Remember; all color components are normalized to the range [0, 1] before
|
|
* computing the result of blending.
|
|
* </para>
|
|
* <section>
|
|
* <title>Examples</title>
|
|
* Blend a non-premultiplied source over a destination with
|
|
* premultiplied alpha:
|
|
* <programlisting>
|
|
* "RGB = ADD(SRC_COLOR*(SRC_COLOR[A]), DST_COLOR*(1-SRC_COLOR[A]))"
|
|
* "A = ADD(SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))"
|
|
* </programlisting>
|
|
* Blend a premultiplied source over a destination with premultiplied alpha:
|
|
* <programlisting>
|
|
* "RGBA = ADD(SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))"
|
|
* </programlisting>
|
|
* </section>
|
|
*
|
|
* The default blend string is:
|
|
* "RGBA = ADD (SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))"
|
|
* That gives normal alpha-blending when the calculated color for the material
|
|
* is in premultiplied form.
|
|
*
|
|
* Returns: TRUE if the blend string was successfully parsed, and the described
|
|
* blending is supported by the underlying driver/hardware. If there
|
|
* was an error, it returns FALSE.
|
|
*
|
|
* Since: 1.0
|
|
*/
|
|
gboolean cogl_material_set_blend (CoglHandle material,
|
|
const char *blend_string,
|
|
GError **error);
|
|
|
|
/**
|
|
* cogl_material_set_blend_constant:
|
|
* @material: A CoglMaterial object
|
|
* @constant_color: The constant color you want
|
|
*
|
|
* When blending is setup to reference a CONSTANT blend factor then
|
|
* blending will depend on the constant set with this function.
|
|
*
|
|
* Since: 1.0
|
|
*/
|
|
void cogl_material_set_blend_constant (CoglHandle material,
|
|
CoglColor *constant_color);
|
|
|
|
/**
|
|
* cogl_material_set_layer:
|
|
* @material: A #CoglHandle for a material object
|
|
* @layer_index: the index of the layer
|
|
* @texture: a #CoglHandle for the layer object
|
|
*
|
|
* In addition to the standard OpenGL lighting model a Cogl material may have
|
|
* one or more layers comprised of textures that can be blended together in
|
|
* order, with a number of different texture combine modes. This function
|
|
* defines a new texture layer.
|
|
*
|
|
* The index values of multiple layers do not have to be consecutive; it is
|
|
* only their relative order that is important.
|
|
*
|
|
* <note>In the future, we may define other types of material layers, such
|
|
* as purely GLSL based layers.</note>
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_layer (CoglHandle material,
|
|
int layer_index,
|
|
CoglHandle texture);
|
|
|
|
/**
|
|
* cogl_material_add_texture:
|
|
* @material: A CoglMaterial object
|
|
* @layer_index: Specifies the layer you want to remove
|
|
*
|
|
* This function removes a layer from your material
|
|
*/
|
|
void cogl_material_remove_layer (CoglHandle material,
|
|
gint layer_index);
|
|
|
|
|
|
/**
|
|
* cogl_material_set_layer_combine:
|
|
* @material: A CoglMaterial object
|
|
* @layer_index: Specifies the layer you want define a combine function for
|
|
* @blend_string: A <link linkend="cogl-Blend-Strings">Cogl blend string</link>
|
|
* describing the desired texture combine function.
|
|
* @error: A #GError that may report parse errors or lack of GPU/driver support.
|
|
* May be %NULL, in which case a warning will be printed out if an
|
|
* error is encountered.
|
|
*
|
|
* If not already familiar; you can refer
|
|
* <link linkend="cogl-Blend-Strings">here</link> for an overview of what blend
|
|
* strings are and there syntax.
|
|
*
|
|
* These are all the functions available for texture combining:
|
|
* <itemizedlist>
|
|
* <listitem>REPLACE(arg0) = arg0</listitem>
|
|
* <listitem>MODULATE(arg0, arg1) = arg0 x arg1</listitem>
|
|
* <listitem>ADD(arg0, arg1) = arg0 + arg1</listitem>
|
|
* <listitem>ADD_SIGNED(arg0, arg1) = arg0 + arg1 - 0.5</listitem>
|
|
* <listitem>INTERPOLATE(arg0, arg1, arg2) =
|
|
* arg0 x arg2 + arg1 x (1 - arg2)</listitem>
|
|
* <listitem>SUBTRACT(arg0, arg1) = arg0 - arg1</listitem>
|
|
* <listitem>
|
|
* DOT3_RGB(arg0, arg1) =
|
|
* <programlisting>
|
|
* 4 x ((arg0[R] - 0.5)) * (arg1[R] - 0.5) +
|
|
* (arg0[G] - 0.5)) * (arg1[G] - 0.5) +
|
|
* (arg0[B] - 0.5)) * (arg1[B] - 0.5))
|
|
* </programlisting>
|
|
* </listitem>
|
|
* <listitem>DOT3_RGBA(arg0, arg1) =
|
|
* <programlisting>
|
|
* 4 x ((arg0[R] - 0.5)) * (arg1[R] - 0.5) +
|
|
* (arg0[G] - 0.5)) * (arg1[G] - 0.5) +
|
|
* (arg0[B] - 0.5)) * (arg1[B] - 0.5))
|
|
* </programlisting>
|
|
* </listitem>
|
|
* </itemizedlist>
|
|
*
|
|
* Refer to the
|
|
* <link linkend="cogl-Blend-String-syntax">color-source syntax</link> for
|
|
* describing the arguments. The valid source names for texture combining
|
|
* are:
|
|
* <itemizedlist>
|
|
* <listitem>
|
|
* TEXTURE: Use the color from the current texture layer
|
|
* </listitem>
|
|
* <listitem>
|
|
* TEXTURE_0, TEXTURE_1, etc: Use the color from the specified texture layer
|
|
* </listitem>
|
|
* <listitem>
|
|
* CONSTANT: Use the color from the constant given with
|
|
* cogl_material_set_layer_constant()
|
|
* </listitem>
|
|
* <listitem>
|
|
* PRIMARY: Use the color of the material as set with cogl_material_set_color()
|
|
* </listitem>
|
|
* <listitem>
|
|
* PREVIOUS: Either use the texture color from the previous layer, or if this
|
|
* is layer 0, use the color of the material as set with
|
|
* cogl_material_set_color()
|
|
* </listitem>
|
|
* </itemizedlist>
|
|
* <refsect2>
|
|
* <title>Example</title>
|
|
* This is effectively what the default blending is:
|
|
* |[
|
|
* RGBA = MODULATE (PREVIOUS, TEXTURE)
|
|
* ]|
|
|
* This could be used to cross-fade between two images, using the alpha
|
|
* component of a constant as the interpolator. The constant color
|
|
* is given by calling cogl_material_set_layer_constant.
|
|
* |[
|
|
* RGBA = INTERPOLATE (PREVIOUS, TEXTURE, CONSTANT[A])
|
|
* ]|
|
|
* </refsect2>
|
|
*
|
|
* <note>You can't give a multiplication factor for arguments as you can
|
|
* with blending.</note>
|
|
*
|
|
* Returns: %TRUE if the blend string was successfully parsed, and the
|
|
* described texture combining is supported by the underlying driver and
|
|
* or hardware. If there was an error, it returns FALSE.
|
|
*
|
|
* Since: 1.0
|
|
*/
|
|
gboolean
|
|
cogl_material_set_layer_combine (CoglHandle material,
|
|
gint layer_index,
|
|
const char *blend_string,
|
|
GError **error);
|
|
|
|
/**
|
|
* cogl_material_set_layer_combine_constant:
|
|
* @material: A CoglMaterial object
|
|
* @layer_index: Specifies the layer you want to specify a constant used
|
|
* for texture combining
|
|
* @constant: The constant color you want
|
|
*
|
|
* When you are using the 'CONSTANT' color source in a layer combine
|
|
* description then you can use this function to define its value.
|
|
*
|
|
* Since 1.0
|
|
*/
|
|
void cogl_material_set_layer_combine_constant (CoglHandle material,
|
|
int layer_index,
|
|
CoglColor *constant);
|
|
|
|
/**
|
|
* cogl_material_set_layer_matrix:
|
|
* @material: A CoglMaterial object
|
|
* @layer_index: the index for the layer inside @material
|
|
* @matrix: the transformation matrix for the layer
|
|
*
|
|
* This function lets you set a matrix that can be used to e.g. translate
|
|
* and rotate a single layer of a material used to fill your geometry.
|
|
*/
|
|
void cogl_material_set_layer_matrix (CoglHandle material,
|
|
int layer_index,
|
|
CoglMatrix *matrix);
|
|
|
|
/**
|
|
* cogl_material_get_layers:
|
|
* @material: a #CoglHandle for a material
|
|
*
|
|
* This function lets you access a materials internal list of layers
|
|
* for iteration.
|
|
*
|
|
* Returns: A list of #CoglHandle<!-- -->'s that can be passed to the
|
|
* cogl_material_layer_* functions. The list is owned by COGL and it
|
|
* should not be modified or freed
|
|
*/
|
|
G_CONST_RETURN GList *cogl_material_get_layers (CoglHandle material);
|
|
|
|
/**
|
|
* cogl_material_get_n_layers:
|
|
* @material: a #CoglHandle for a material
|
|
*
|
|
* Retrieves the number of layers defined for the given @material
|
|
*
|
|
* Returns: the number of layers
|
|
*
|
|
* Since: 1.0
|
|
*/
|
|
int cogl_material_get_n_layers (CoglHandle material);
|
|
|
|
/**
|
|
* CoglMaterialLayerType:
|
|
* @COGL_MATERIAL_LAYER_TYPE_TEXTURE: The layer represents a
|
|
* <link linkend="cogl-Textures">Cogl texture</link>
|
|
*
|
|
* Available types of layers for a #CoglMaterial. This enumeration
|
|
* might be expanded in later versions.
|
|
*
|
|
* Since: 1.0
|
|
*/
|
|
typedef enum { /*< prefix=COGL_MATERIAL_LAYER_TYPE >*/
|
|
COGL_MATERIAL_LAYER_TYPE_TEXTURE
|
|
} CoglMaterialLayerType;
|
|
|
|
/**
|
|
* cogl_material_layer_get_type:
|
|
* @layer_handle: A #CoglHandle for a material layer
|
|
*
|
|
* Retrieves the type of the layer
|
|
*
|
|
* Currently there is only one type of layer defined:
|
|
* %COGL_MATERIAL_LAYER_TYPE_TEXTURE, but considering we may add purely GLSL
|
|
* based layers in the future, you should write code that checks the type
|
|
* first.
|
|
*
|
|
* Returns: the type of the layer
|
|
*/
|
|
CoglMaterialLayerType cogl_material_layer_get_type (CoglHandle layer_handle);
|
|
|
|
/**
|
|
* cogl_material_layer_get_texture:
|
|
* @layer_handle: A #CoglHandle for a material layer
|
|
*
|
|
* This lets you extract a CoglTexture handle for a specific layer.
|
|
*
|
|
* <note>In the future, we may support purely GLSL based layers which will
|
|
* likely return %COGL_INVALID_HANDLE if you try to get the texture.
|
|
* Considering this, you can call cogl_material_layer_get_type first,
|
|
* to check it is of type %COGL_MATERIAL_LAYER_TYPE_TEXTURE.</note>
|
|
*
|
|
* Returns: a #CoglHandle for the texture inside @layer_handle
|
|
*/
|
|
CoglHandle cogl_material_layer_get_texture (CoglHandle layer_handle);
|
|
|
|
/**
|
|
* cogl_material_layer_get_min_filter:
|
|
* @layer_handle: a #CoglHandle for a material layer
|
|
*
|
|
* Query the currently set downscaling filter for a cogl material layer.
|
|
*
|
|
* Returns: the current downscaling filter for a cogl material layer.
|
|
*/
|
|
CoglMaterialFilter cogl_material_layer_get_min_filter (CoglHandle layer_handle);
|
|
|
|
/**
|
|
* cogl_material_layer_get_mag_filter:
|
|
* @layer_handle: a #CoglHandle for a material layer
|
|
*
|
|
* Query the currently set downscaling filter for a cogl material layer.
|
|
*
|
|
* Returns: the current downscaling filter for a cogl material layer.
|
|
*/
|
|
CoglMaterialFilter cogl_material_layer_get_mag_filter (CoglHandle layer_handle);
|
|
|
|
/**
|
|
* cogl_material_set_layer_filters:
|
|
* @handle: a #CoglHandle to a material.
|
|
* @layer_index: the layer number to change.
|
|
* @min_filter: the filter used when scaling a texture down.
|
|
* @mag_filter: the filter used when magnifying a texture.
|
|
*
|
|
* Changes the decimation and interpolation filters used when a texture is
|
|
* drawn at other scales than 100%.
|
|
*/
|
|
void cogl_material_set_layer_filters (CoglHandle handle,
|
|
gint layer_index,
|
|
CoglMaterialFilter min_filter,
|
|
CoglMaterialFilter mag_filter);
|
|
|
|
G_END_DECLS
|
|
|
|
#endif /* __COGL_MATERIAL_H__ */
|
|
|