GLSL Shader in Maya Part 2: Textures

-

Welcome to a new chapter in our experiment to make Maya work as a shader editor.
I'm going to show you a simple shader to load textures using the second method I've shown you in the previous article.
The code is pretty much self explanatory, look at the comments to find out more.

basic_texture.ogsfx 
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
// Tell included shaders to use OGSFX semantics and streams:
#define OGSFX 1

//########################### UNIFORMS ###########################
// Uniform parameter handling
// Loads the uniforms from all shader stage files
#define HIDE_OGSFX_UNIFORMS 0
#define HIDE_OGSFX_STREAMS 1
#define HIDE_OGSFX_CODE 1

#include "basic_texture.glslv"
#include "basic_texture.glslf"

//########################### ATTRIBUTES ###########################
// Input stream handling:
// Loads the attribute streams from all shader stage files
#define HIDE_OGSFX_UNIFORMS 1
#define HIDE_OGSFX_STREAMS 0
#define HIDE_OGSFX_CODE 1

#include "basic_texture.glslv"
#include "basic_texture.glslf"

//########################### FUNCTION ###########################
// Code handling:
// We need to load the vertex stage and fragment stage in two
// different GLSLShader blocks in order to specify them in the
// technique definition below:
#define HIDE_OGSFX_UNIFORMS 1
#define HIDE_OGSFX_STREAMS 1
#define HIDE_OGSFX_CODE 0

// Vertex shader.
GLSLShader VS
{
#include "basic_texture.glslv"
}

// Fragment shader.
GLSLShader FS
{
#include "basic_texture.glslf"
}

// Techniques.
technique Main
{
    pass p0
    {
        VertexShader (in vs_input, out vs_out) = VS;
        PixelShader (in fs_input, out fs_out) = FS;
    }
}

basic_texture.glslv (vertex shader)
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
//########################### GLSL VERSION ###########################
//If it's not a Maya OGSFX Shader set the GLSL version for common GLSL shaders
#if !OGSFX
#version 330
#endif

//########################### UNIFORMS ###########################
//Put here OGSFX uniform specific code
#if !HIDE_OGSFX_UNIFORMS
#if OGSFX

uniform mat4 MVP : WorldViewProjection;

#else

uniform mat4 MVP;

#endif //OGSFX
#endif // HIDE_OGSFX_UNIFORMS

//########################### ATTRIBUTES ###########################
//Put here OGSFX attribute specific code
#if !HIDE_OGSFX_STREAMS
#if OGSFX

attribute vs_input
{
    vec3 Position : POSITION;
    vec2 UV : TEXCOORD0;
    vec3 Normal : NORMAL;
};

// The vertex shader ouput and also the pixel shader input
attribute vs_out
{
    vec2 outUV;
};

#else

in vec3 Position;

#endif //OGSFX
#endif //HIDE_OGSFX_STREAMS

//########################### FUNCTION ###########################
//Put here main function
#if !HIDE_OGSFX_CODE

void main()
{
    outUV = vec2(UV.x, 1.0 - UV.y);
    gl_Position = MVP * vec4(Position, 1);
}

#endif //HIDE_OGSFX_STREAMS

basic_texture.glslf (fragment shader)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
//########################### GLSL VERSION ###########################
//If it's not a Maya OGSFX Shader set the GLSL version for common GLSL shaders
#if !OGSFX
#version 330
#endif

//########################### UNIFORMS ###########################
//Put here OGSFX uniform specific code
#if !HIDE_OGSFX_UNIFORMS

#if OGSFX
uniform texture2D gTexture <
    string UIName = "Texture";
    string UIGroup = "Editable Parameters";
    int UIOrder = 1;
    string ResourceName = "centaur.jpg";
    string ResourceType = "2D";
    // string UIWidget = "None";
    string UIDesc = "Special Mipped Stripe";
>;
#endif

//Anytime you add a texture,, make sure you also add a sampler2D otherwise Maya will crash
uniform sampler2D gTextureSampler
#if OGSFX
    = sampler_state {
        Texture = <gTexture>;
    }
#endif
    ;


#endif //HIDE_OGSFX_UNIFORMS

//########################### ATTRIBUTES ###########################
//Put here OGSFX attribute specific code
#if !HIDE_OGSFX_STREAMS
#if OGSFX
attribute fs_input
{
    vec2 outUV : TEXCOORD0;
};

attribute fs_out
{
    vec4 out_color : COLOR0;
};

#else 

in vec2 outUV;
out vec4 out_color;

#endif //OGSFX
#endif //HIDE_OGSFX_STREAMS

//########################### FUNCTION ###########################
//Put here main function
#if !HIDE_OGSFX_CODE

void main()
{

    float ambientStrength = 0.1;

    out_color = ambientStrength * texture2D(gTextureSampler, outUV);
}

#endif //HIDE_OGSFX_STREAMS

Comments

Post a Comment

Popular posts from this blog

GLSL Shader in Maya Part 1

-
Image
Maya to act like an (expensive) shader editor There aren't many shader editors out there, not as many as it used to be in the early 2000s when AMD had RenderMonkey and Nvidia had FX Composer. They were pretty good softwares in my own humble opinion and it's a pity they have been discontinued. These days we have Shadertoy but to be honest I prefer native applications, yes I'm old school! I've always known that Maya supports HLSL and GLSL shaders in Viewport 2.0 so I've started to think that it would be really cool to use it like a shader editor. But it's not as simple as I would have expected, the documentation around the net is pretty sparse so it's a matter of trials and errors. Why GLSL and not HLSL? I have nothing against HLSL, in fact I use it extensively in Unity (well to be precise I use Cg which is NVidia version of HLSL). I've decided to go with GLSL simply because is more portable and I like to use Maya on Linux for my person...
Read more

Unity Shader: Toon Water Shader

-
Image
  I'm a huge fan of Studio Ghibli movies and I've always wanted to replicate their visual style in a video game. In this post I'll tell you how I emulate as close as possible, the look of the water we all love in Studio Ghibli movies. Before we continue, I'd like to thank Roystan and Harry Alisavakis for their tutorials on toon water  and grab pass shaders which gave me the kickstart to develop my own water shader. Features I wanted my shader to be quick and easy to insert in a scene, so all you need is just a flat plane that will be our water surface and some kind of terrain with depth to contain our water. The shader will have the following features: animated vertex displacement animated fake refraction selective planar reflection animated normal maps animated foam How it works We can subdivide the shader into 5 steps: Vertex displacement - use a simple vertex displacement map to generate waves moving the vertices of the flat plane along the y-axis. Depth based w...
Read more

Unity Shader: Spherical Mask Dissolve

-
Image
Spherical Mask Dissolve Shader This shader is the combination of the two previous shader, the Dissolve shader and the Spherical Mask shader to get a "reveal world" kind of shader, something like you have experienced in games like Beyond Eyes . If you remember, in the Dissolve shader we used a  _DissolveTexture  to get a dissolve_value . Because the dissolve_value is in the range of (0,1) we needed an _Amount value to be subtracted from the dissolve_value so that the clip() function can discard all the pixels that has a dissolve_value < 0. In the Spherical Mask Dissolve shader we don't have an _Amount value, instead we have to compute it! To compute the _Amount value (that in this shader is called amount) , we use the technique showed in the Spherical Mask Shader. In the Spherical Mask Shader we checked if a pixel was inside of the player radius of action, if it was we color it, if it wasn't we let it in grayscale. Here we use the same logic to define ...
Read more