Textures

/* Declaration */
GPUTexture m_texture;

/* Loading a .png file */
Texture::CreateFromRGBAFile(&m_texture, "myimage.png");
/* Set a default sampler (trilinear) */
Texture::SetParameters(&m_texture, SamplerDesc::Default2D());

/* Bind before renderin */
Texture::BindToUnit(m_texture,0u);

How to create an empty texture for a framebuffer:

TextureDesc desc = {};
desc.width = 256u;
desc.height = 256u;
desc.pixeltype = GL_UNSIGNED_BYTE;
desc.internal = GL_RGBA8;
desc.format = GL_RGBA;

Texture::CreateEmpty2D(&m_simple_texture,desc);

TextureDesc Description

struct SamplerDesc

OpenGL texture sampler description data structure.

Public Members

uint32_t wrap_u = 0

OpenGL flag for texture wrapping U

uint32_t wrap_v = 0

OpenGL flag for texture wrapping V

uint32_t wrap_w = 0

OpenGL flag for texture wrapping W

uint32_t minification = 0

OpenGL flag for texture minification

uint32_t magnification = 0

OpenGL flag for texture magnification

bool mipmap = false

is mipmap generation enabled ?

bool anisotropy = false

is anisotropic filtering enabled ? does the the hardware supports it ?

Public Static Functions

static SamplerDesc Default2D()

Create a 2D default sampler object.

Create a 2D sampler with the following parameters:

  • wrap : GL_REPEAT

  • mag : GL_LINEAR

  • min : GL_LINEAR_MIPMAP_LINEAR

  • mips : true

Parameters:

s – A pointer to a GPUSampler

static SamplerDesc Default3D()

Create a 3D default sampler object.

Create a 2D sampler with the following parameters:

  • wrap : GL_REPEAT

  • mag : GL_LINEAR

  • min : GL_LINEAR_MIPMAP_LINEAR

  • mips : true

Parameters:

s – A pointer to a GPUSampler

static SamplerDesc Create2D(uint32_t wrap, uint32_t mag, uint32_t min, bool mips)

Create a 2D sampler.

Parameters:

  • wrap – Wrap parameter for texture coordinates s,t in

    • GL_CLAMP_TO_EDGE

    • GL_MIRRORED_REPEAT

    • GL_REPEAT

  • mag – Texture magnification flag (used when pixel maps to an area less than or equal to one texture element )

    • GL_NEAREST : nearest manhattan distance value to the center of the textured pixel.

    • GL_LINEAR : weighted average of the four elements thats are closest to the center of the textured pixel.

  • min – Texture minification flag (used when pixel maps to an area greater than one texture element )

    • GL_NEAREST : nearest manhattan distance value to the center of the textured pixel.

    • GL_LINEAR : weighted average of the four elements thats are closest to the center of the textured pixel.

    • GL_NEAREST_MIPMAP_NEAREST : closest mipmap matching the size of the texture pixel and uses the nearest criterion.

    • GL_NEAREST_MIPMAP_LINEAR : closest mipmap matching the size of the texture pixel and uses the weighted average criterion.

    • GL_LINEAR_MIPMAP_NEAREST : choses the two closest mipmaps and averages the two nearest values for the textured pixel.

    • GL_LINEAR_MIPMAP_LINEAR : choses the two closest mipmaps and averages the two averaged values for the final textured pixel.

  • mips – Enables MipMapping

static SamplerDesc Create3D(uint32_t wrap, uint32_t mag, uint32_t min, bool mips)

Create a 3D sampler.

Parameters:

  • wrap – Wrap parameter for texture coordinates s,t,u in

    • GL_CLAMP_TO_EDGE

    • GL_MIRRORED_REPEAT

    • GL_REPEAT

  • mag – Texture magnification flag (used when pixel maps to an area less than or equal to one texture element )

    • GL_NEAREST : nearest manhattan distance value to the center of the textured pixel.

    • GL_LINEAR : weighted average of the four elements thats are closest to the center of the textured pixel.

  • min – Texture minification flag (used when pixel maps to an area greater than one texture element )

    • GL_NEAREST : nearest manhattan distance value to the center of the textured pixel.

    • GL_LINEAR : weighted average of the four elements thats are closest to the center of the textured pixel.

    • GL_NEAREST_MIPMAP_NEAREST : closest mipmap matching the size of the texture pixel and uses the nearest criterion.

    • GL_NEAREST_MIPMAP_LINEAR : closest mipmap matching the size of the texture pixel and uses the weighted average criterion.

    • GL_LINEAR_MIPMAP_NEAREST : choses the two closest mipmaps and averages the two nearest values for the textured pixel.

    • GL_LINEAR_MIPMAP_LINEAR : choses the two closest mipmaps and averages the two averaged values for the final textured pixel.

  • mips – Enables MipMapping

static SamplerDesc Create2DAnisotropic(uint32_t wrap)

Create a 2D sampler and prepare anisotropic mipmapping if hardware supports it.

Texture minification and magnification are automatically set. If hardware doesn’t support anisotropy, switch to trilinear. REQUIRES GL BACKEND 4.6

Parameters:

wrap – Wrap parameter for texture coordinates s,t,u in

  • GL_CLAMP_TO_EDGE

  • GL_MIRRORED_REPEAT

  • GL_REPEAT

struct TextureDesc

OpenGL texture description data structure.

Public Members

uint32_t width = 0

OpenGL GLuint texture Width (pixels)

uint32_t height = 0

OpenGL GLuint texture Height (pixels)

uint32_t depth = 0

OpenGL GLuint texture Depth or Layers (pixels/layers)

uint32_t internal = 0

OpenGL GLuint texture sized format (GL_RGBA8, GL_R32F, etc.)

uint32_t format = 0

OpenGL 3.3 GLuint texture format (GL_RED, GL_RGB, GL_RGBA, etc.)

uint32_t pixeltype = 0

OpenGL 3.3 GLuint texture pixel data type (GL_UNSIGNED_BYTE, GL_FLOAT, etc.)

Public Static Functions

static TextureDesc Create2D(uint32_t width, uint32_t height, uint32_t internal)

Returns a 2D texture description (width, height, internal sized format)

static TextureDesc Create2D(uint32_t width, uint32_t height, uint32_t internal, uint32_t format, uint32_t pixeltype)

Returns a 2D texture description (width, height, internal sized format, format, pixel data type)

static TextureDesc Create3D(uint32_t width, uint32_t height, uint32_t depth, uint32_t internal)

Returns a 3D texture description (width, height, depth, internal sized format)

static TextureDesc Create3D(uint32_t width, uint32_t height, uint32_t depth, uint32_t internal, uint32_t format, uint32_t pixeltype)

Returns a 3D texture description (width, height, depth, internal sized format, format, pixel data type)

static TextureDesc CreateCubeMap(uint32_t size, uint32_t internal)

Returns a Cubemap texture description (cube size, internal sized format)

static TextureDesc CreateCubeMap(uint32_t size, uint32_t internal, uint32_t format, uint32_t pixeltype)

Returns a Cubemap texture description (cube size, internal sized format, format, pixel data type)

struct GPUTexture

OpenGL texture data structure.

Public Members

uint32_t id = 0

OpenGL GLuint texture ID

uint32_t levels = 0

OpenGL texture levels (MipLevels)

uint32_t type = 0

OpenGL texture Type (2D,3D,Array,…)

uint32_t samples = 0

OpenGL texture samples (Multisampled)

TextureDesc desc

Texture description

Texture API Description

namespace Texture

Functions

void CreateEmpty2D(GPUTexture *t, const TextureDesc &desc)

Create a empty 2D texture.

Parameters:

  • t – A GPUTexture pointer

  • desc – The requested texture description (Required: desc.width, desc.height, desc.internal, (gl3.3 desc.format), (gl3.3 desc.pixeltype))

void CreateEmpty3D(GPUTexture *t, const TextureDesc &desc)

Create a empty 3D texture.

Parameters:

  • t – A GPUTexture pointer

  • desc – The requested texture description (Required: desc.width, desc.height, desc.depth, desc.internal, (gl3.3 desc.format), (gl3.3 desc.pixeltype))

void CreateEmpty2DArray(GPUTexture *t, const TextureDesc &desc)

Create a empty 2D texture array.

Parameters:

  • t – A GPUTexture pointer

  • desc – The requested texture description (Required: desc.width, desc.height, desc.depth, desc.internal, (gl3.3 desc.format), (gl3.3 desc.pixeltype))

void CreateEmptyCubemap(GPUTexture *t, const TextureDesc &desc)

Create a empty 2D cubemap texture.

Parameters:

  • t – A GPUTexture pointer

  • desc – The requested texture description (Required: desc.width, desc.internal, (gl3.3 desc.format), (gl3.3 desc.pixeltype))

void CreateEmpty2DMultisample(GPUTexture *t, const TextureDesc &desc, uint8_t samples)

Create a empty 2D multisampled texture.

Parameters:

  • t – A GPUTexture pointer

  • desc – The requested texture description (Required: desc.width, desc.height, desc.internal, (gl3.3 desc.format), (gl3.3 desc.pixeltype))

  • samples – Number of samples in the texture

void CreateEmpty2DArrayMultisample(GPUTexture *t, const TextureDesc &desc, uint8_t samples)

Create a empty 2D multisampled texture array.

Parameters:

  • t – A GPUTexture pointer

  • desc – The requested texture description (Required: desc.width, desc.height, desc.internal, (gl3.3 desc.format), (gl3.3 desc.pixeltype))

  • samples – Number of samples in the texture

void CreateFromRGBAFile(GPUTexture *t, const std::string &filepath, bool flip = true)

Create a texture from a rgba file (png, jpg)

Parameters:

  • t – A GPUTexture pointer

  • filepath – The path to the .hdr file

  • flip – Performs a vertical flip of the texture content

void CreateFromHDRIFile(GPUTexture *t, const std::string &filepath, bool flip = true)

Create a texture from hdri file.

Parameters:

  • t – A GPUTexture pointer

  • filepath – The path to the .hdr file

  • flip – Performs a vertical flip of the texture content

void CreateFromCopy2D(GPUTexture *t, const GPUTexture &texture_to_copy)

Create a copy of a 2D texture.

void CreateFromCopy3D(GPUTexture *t, const GPUTexture &texture_to_copy)

Create a copy of a 3D texture.

void Destroy(GPUTexture *t)

Destroy gpu texture ressource.

void Copy(const GPUTexture &source, const GPUTexture &target)

Copy content from another gpu texture ressource.

void SetParameters(GPUTexture *t, const SamplerDesc &s)

Apply sampler parameters to the input texture.

void SetParameters(GPUTexture *t, uint32_t wrap, uint32_t mag, uint32_t min, bool mips)

Manually apply specific parameters to the input texture.

void SetBorderColor(GPUTexture *t, float *c)

Manually set the border color of the input texture.

void GenerateMipmap(GPUTexture *t)

Manually generate the mipmap chain of the input texture.

void BindToUnit(const GPUTexture &t, uint32_t unit)

Bind the texture ressource to the binding point.

void BindImageTexture(const GPUTexture &t, uint32_t unit, uint32_t access, uint32_t level = 0u)

Bind the image texture ressource to the binding point with the following access (used in compute shader)

void BindImageTextureLayered(const GPUTexture &t, uint32_t unit, uint32_t layer, uint32_t access, uint32_t level = 0u)

Bind the layered image texture ressource to the binding point with the following access (used in compute shader)