add shader on dolphin

[Air_maX]

Good morning to you all!
Well, I warn right now, I’m French, and a bad English student (no, no there is no connection between these two facts    )...so it’s google that translates (yes, bad)

Then, sorry if I’m writing in the wrong section, I’m a young puppy here, I don’t know yet where I have to pee  

I’ve been working on a cocktail table that will contain several emulators, including Dolphin. I try to use a shader that works with all emulators.... except Dolphin    .
[color=#000000]The goal of this shader is to duplicate the image of the game in mirror, so that two players face to face each have the image of the game in the right direction. I have tinkered with an image to make you understand what the shader does:[/color]



[color=#000000]When I use it everywhere, no problem.[/color]
[color=#000000]When I use it on Dolphin, I get this message:[/color]

Code:

error c3001 no program defined

Does anyone here know (at least a little) about shaders?

Thank you in advance.

[MayImilae]

Whether or not a shader or injection method will work depends heavily on the specific details of them... which you haven't provided any of yet. So it's impossible for us to help you with it until you share those details with us. So um, share the shader and your injection method, and we'll see?

[Air_maX]

Very useful answer  !
Here is the code of the shader :

Code:

// Cocktail Mirror Tate
// by hunterk
// license: public domain

#pragma parameter width "Cocktail Width" 1.0 0.0 2.0 0.01
#pragma parameter height "Cocktail Height" 0.49 0.0 2.0 0.01
#pragma parameter x_loc "Cocktail X Mod" 0.0 -2.0 2.0 0.01
#pragma parameter y_loc "Cocktail Y Mod" 0.51 -2.0 2.0 0.01

#if defined(VERTEX)

#if __VERSION__ >= 130
#define COMPAT_VARYING out
#define COMPAT_ATTRIBUTE in
#define COMPAT_TEXTURE texture
#else
#define COMPAT_VARYING varying
#define COMPAT_ATTRIBUTE attribute
#define COMPAT_TEXTURE texture2D
#endif

#ifdef GL_ES
#define COMPAT_PRECISION mediump
#else
#define COMPAT_PRECISION
#endif

COMPAT_ATTRIBUTE vec4 VertexCoord;
COMPAT_ATTRIBUTE vec4 COLOR;
COMPAT_ATTRIBUTE vec4 TexCoord;
COMPAT_VARYING vec4 COL0;
COMPAT_VARYING vec4 TEX0;
COMPAT_VARYING vec2 t1;

vec4 _oPosition1;
uniform mat4 MVPMatrix;
uniform COMPAT_PRECISION int FrameDirection;
uniform COMPAT_PRECISION int FrameCount;
uniform COMPAT_PRECISION vec2 OutputSize;
uniform COMPAT_PRECISION vec2 TextureSize;
uniform COMPAT_PRECISION vec2 InputSize;

// compatibility #defines
#define vTexCoord TEX0.xy
#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
#define OutSize vec4(OutputSize, 1.0 / OutputSize)

#ifdef PARAMETER_UNIFORM
uniform COMPAT_PRECISION float width, height, x_loc, y_loc;
#else
#define width 1.0
#define height 0.49
#define x_loc 0.0
#define y_loc 0.51
#endif

void main()
{
   gl_Position = MVPMatrix * VertexCoord;
   TEX0.xy = TexCoord.xy;
    TEX0.xy = TEX0.xy - 0.5 * InputSize / TextureSize;
    TEX0.xy = TEX0.xy * vec2(1. / width, 1. / height);
    TEX0.xy = TEX0.xy + 0.5 * InputSize / TextureSize;
    t1.xy = 1.* InputSize / TextureSize - TEX0.xy;
    TEX0.xy -= vec2(x_loc, y_loc) * InputSize / TextureSize;
    t1.xy -= vec2(x_loc, y_loc) * InputSize / TextureSize;
}

#elif defined(FRAGMENT)

#ifdef GL_ES
#ifdef GL_FRAGMENT_PRECISION_HIGH
precision highp float;
#else
precision mediump float;
#endif
#define COMPAT_PRECISION mediump
#else
#define COMPAT_PRECISION
#endif

#if __VERSION__ >= 130
#define COMPAT_VARYING in
#define COMPAT_TEXTURE texture
out COMPAT_PRECISION vec4 FragColor;
#else
#define COMPAT_VARYING varying
#define FragColor gl_FragColor
#define COMPAT_TEXTURE texture2D
#endif

uniform COMPAT_PRECISION int FrameDirection;
uniform COMPAT_PRECISION int FrameCount;
uniform COMPAT_PRECISION vec2 OutputSize;
uniform COMPAT_PRECISION vec2 TextureSize;
uniform COMPAT_PRECISION vec2 InputSize;
uniform sampler2D Texture;
COMPAT_VARYING vec4 TEX0;
COMPAT_VARYING vec2 t1;

// compatibility #defines
#define Source Texture
#define vTexCoord TEX0.xy

#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
#define OutSize vec4(OutputSize, 1.0 / OutputSize)

void main()
{
    vec4 screen1 = COMPAT_TEXTURE(Source, vTexCoord);
    screen1 *= float(vTexCoord.x > 0.0001) * float(vTexCoord.y > 0.0001) * float(vTexCoord.x < 0.9999) * float(vTexCoord.y < 0.9999);
    vec4 screen2 = COMPAT_TEXTURE(Source, t1);
    screen2 *= float(t1.x > 0.0001) * float(t1.y > 0.0001) * float(t1.x < 0.9999) * float(t1.y < 0.9999);
    FragColor = screen1 + screen2;
}
#endif

The injection method is (I didn’t think there were many) indicated in the attached photos:



And here is the result when starting a game:



This code has been written for retroarch, and it works very well under retroarch.

Three hypotheses :
- Or Dolphin does not recognize certain functions specific to Retroarch
- Or Dolphin does not recognize certain variables specific to Retroarch
- I may not know anything about it and that is not the problem at all

[DJBarry004]

The Dolphin version used in RetroArch is not fully the same as the official dev builds afaik. So yeah, expect things like this to happen.

You will have to modify the shader so it can work with official Dolphin builds.

[Air_maX]

I suspected a little that we would have to grope a little
Where can I find documentation, or help on how to write a shader for Dolphin?