Dealing with custom shaders and make them generic is not an easy task. There are many things to consider for a shader because, after all, the shader is the responsible to process all the data send to the GPU (mesh, materials, textures, lighting) to generate the final frame.
Dealing with custom shaders and making them generic is not an easy task. There are many things to consider for a shader because, after all, the shader is responsible for processing all the data sent to the GPU (e.g. mesh, materials, textures, lighting) to generate the final frame.
Find an unified generic shader to deal with all kind of stuff is very complicated and, after analyzing some of the big engines out there, I decided to go for a custom uber-shader-based solution.
Finding a unified generic shader to deal with all kinds of stuff is very complicated and, after analyzing some of the big engines out there, I decided to go for a custom uber-shader-based solution.
By default, raylib shader struct support the following data:
By default, raylib's shader struct supports the following data:
```c
typedef struct Shader {
unsigned int id; // Shader program id
@ -28,22 +28,22 @@ typedef struct Shader {
As you can see, most of the location points are pre-defined **on shader loading**; custom shaders developed for raylib must follow those conventions.
On shader loading, following fixed location names are expected for maps:
On shader load, the following fixed location names are expected for maps:
```glsl
uniform sampler2D texture0; // GL_TEXTURE0
uniform sampler2D texture1; // GL_TEXTURE1
uniform sampler2D texture2; // GL_TEXTURE2
```
Shaders are also directly related to Material struct:
Shaders are also directly related to the Material struct:
```c
// Material type
typedef struct Material {
Shader shader; // Standard shader (supports 3 map textures)
Texture2D texDiffuse; // Diffuse texture (binded to shader mapTexture0Loc)
Texture2D texNormal; // Normal texture (binded to shader mapTexture1Loc)
Texture2D texSpecular; // Specular texture (binded to shader mapTexture2Loc)
Texture2D texDiffuse; // Diffuse texture (bound to shader mapTexture0Loc)
Texture2D texNormal; // Normal texture (bound to shader mapTexture1Loc)
Texture2D texSpecular; // Specular texture (bound to shader mapTexture2Loc)
Color colDiffuse; // Diffuse color
Color colAmbient; // Ambient color
@ -52,12 +52,12 @@ typedef struct Material {
float glossiness; // Glossiness level (Ranges from 0 to 1000)
} Material;
```
Where three texture maps (texDiffuse, texNormal, texSpecular) are binded to shader location points.
Where three texture maps (texDiffuse, texNormal, texSpecular) will bind to shader location points.
On drawing, depending on textures assigned to material and selected shader, they are internally binded on drawing or not:
When drawing, textures are internally bound or not depending on the selected shader and material:
```c
// Default material loading example
Material material = LoadDefaultMaterial(); // Default shader assigned to material (supports only diffuse map)
Material material = LoadDefaultMaterial(); // Default shader assigned to material (supports only diffuse map)
material.texDiffuse = LoadTexture("wood_diffuse.png"); // texture unit 0 activated (available in material shader)
material.texSpecular = LoadTexture("wood_specular.png"); // texture unit 2 activated (available in material shader)
material.texSpecular = LoadTexture("wood_specular.png"); // texture unit 2 NOT activated (not available in material shader)
```
Despite its name on material struct (`texDiffuse`, `texNormal`, `texSpecular`), user is free to use those maps in any way inside the **custom** shader.
Despite its name on material struct (`texDiffuse`, `texNormal`, `texSpecular`), the user is free to use those maps in any way inside the **custom** shader.
Michael Campagnaro
8 anos atrás