# Glsl shader not showing any errors, but neither any output

**URL:** <https://discourse.processing.org/t/glsl-shader-not-showing-any-errors-but-neither-any-output/39628>\
**Category:** Coding Questions\
**Created:** [November 8, 2022, 3:40pm UTC](https://discourse.processing.org/t/glsl-shader-not-showing-any-errors-but-neither-any-output/39628 "2022-11-08T15:40:06Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![clankill3r](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/clankill3r/32/1098_2.png) [@clankill3r](https://discourse.processing.org/u/clankill3r)\
**Post date:** [November 8, 2022, 3:40pm UTC](https://discourse.processing.org/t/glsl-shader-not-showing-any-errors-but-neither-any-output/39628/1 "2022-11-08T15:40:07Z")

</div>

When I use this shader, I see no errors, but neither any color is drawn.

vert:

```auto
#version 330 core
layout (location = 0) in vec3 aPos;
  
out vec4 vertexColor;

void main()
{
    gl_Position = vec4(aPos, 1.0);
    vertexColor = vec4(0.5, 0.0, 0.0, 1.0);
}

```

frag:

```auto
#version 330 core
out vec4 FragColor;
  
in vec4 vertexColor;

void main()
{
    FragColor = vertexColor;
} 

```

```auto
PShader s_msdf; 

void settings() {
  size(600, 600, P2D);
}

void setup() {
  s_msdf = loadShader("msdf.frag", "msdf.vert");
}

void draw() {
  shader(s_msdf);
  fill(0);
  rect(0, 0, 500, 500);
  resetShader();
}

```

How can this be fixed? Normally I write my shaders more in the ‘old’ style. But it’s so outdated.

---

<div class="post-metadata">

**Author:** ![scudly](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/scudly/32/5597_2.png) [@scudly](https://discourse.processing.org/u/scudly)\
**Post date:** [November 8, 2022, 9:49pm UTC](https://discourse.processing.org/t/glsl-shader-not-showing-any-errors-but-neither-any-output/39628/2 "2022-11-08T21:49:44Z")

</div>

Try this instead:

```auto
PShader s_msdf; 

void settings() {
  size(600, 600, P2D);
}

void setup() {
  s_msdf = new PShader( g.parent, vertSrc, fragSrc );
}

void draw() {
  shader(s_msdf);
  fill(0);
  rect(0, 0, 500, 500);
  resetShader();
}

String[] vertSrc = {"""
#version 330 core
uniform mat4 transformMatrix;
layout (location = 0) in vec4 position;
  
out vec4 vertexColor;

void main()
{
    gl_Position = transformMatrix * position;
    vertexColor = vec4(0.5, 0.0, 0.0, 1.0);
}
"""};

String[] fragSrc = {"""
#version 330 core
out vec4 FragColor;
  
in vec4 vertexColor;

void main()
{
    FragColor = vertexColor;
}
"""};

```

---

<div class="post-metadata">

**Author:** ![clankill3r](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/clankill3r/32/1098_2.png) [@clankill3r](https://discourse.processing.org/u/clankill3r)\
**Post date:** [November 14, 2022, 12:32pm UTC](https://discourse.processing.org/t/glsl-shader-not-showing-any-errors-but-neither-any-output/39628/3 "2022-11-14T12:32:34Z")

</div>

Thank you, that works.