glDisableVertexAttribArray works in one Visual Studio solution, but not another - c++

Question

I am having a very strange occurrence where glDisableVertexAttribArray works in my one solution but when I get the solution from my Perforce repository, it doesn't run and throws an assert.
I checked out this forum question but it, unfortunately, didn't solve my problem. This is for shadow mapping that I have been working on and when I try to render things to the depth buffer and then disable the vertex attributes, it throws an error.
Here's how my code is laid out:
glUseProgram(shaderProgram);
glUniform1i(u_diffuseTextureLocation, 0);
glUniform1i(u_shadowMapLocation, 1);
[...]
glUseProgram(shaderProgram);
[Render some stuff to depth buffer]
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
glBindVertexArray(0);
glDisableVertexAttibArray(a_normalAttribLocation); // This gives the GL_INVALID_OPERATION
// enum
And here's the vertex shader in that program:
#version 430 core
uniform mat4 u_projection;
uniform mat4 u_view;
uniform mat4 u_model;
uniform mat4 u_lightSpaceMat;
in vec3 a_position;
in vec3 a_normal;
in vec2 a_texture;
out VS_OUT {
vec3 v_fragPos;
vec3 v_normal;
vec2 v_texCoords;
vec4 v_fragPosLightSpace;
} vs_out;
void main()
{
gl_Position = u_projection * u_view * u_model * vec4(a_position, 1.0);
vs_out.v_fragPos = (u_model * vec4(a_position, 1.0)).xyz;
vs_out.v_normal = transpose(inverse(mat3(u_model))) * a_normal;
vs_out.v_texCoords = a_texture;
vs_out.v_fragPosLightSpace = u_lightSpaceMat * vec4(vs_out.v_fragPos, 1.0);
}
And the fragment shader in the program:
#version 430 core
uniform sampler2D u_shadowMap;
uniform sampler2D u_diffuseTexture;
uniform vec3 u_lightPos;
uniform vec3 u_viewPos;
in VS_OUT {
vec3 v_fragPos;
vec3 v_normal;
vec2 v_texCoords;
vec4 v_fragPosLightSpace;
} fs_in;
out vec4 fragColor;
float shadowCalculation(vec4 fragPosLightSpace, vec3 normal, vec3 lightDir)
{
// perform perspective divide
vec3 projCoords = fragPosLightSpace.xyz / fragPosLightSpace.w;
// transform to [0,1] range
projCoords = projCoords * 0.5 + 0.5;
// Get closest depth value from light's perspective (using [0,1] range
// fragPosLight as coords)
float closestDepth = texture(u_shadowMap, projCoords.xy).r;
// Get depth of current fragment from lights perspective
float currentDepth = projCoords.z;
float bias = max(0.05 * (1.0 - dot(normal, lightDir)), 0.005);
// Percentage closer filtering
float shadow = 0.0;
vec2 texelSize = 1.0 / textureSize(u_shadowMap, 0);
for (int x = -1; x <= 1; ++x)
{
for (int y = -1; y <= 1; ++y)
{
float pcfDepth = texture(u_shadowMap, projCoords.xy + vec2(x, y) * texelSize).r;
shadow += currentDepth - bias > pcfDepth ? 1.0 : 0.0;
}
}
shadow /= 9.0;
return shadow;
}
void main()
{
vec3 color = texture(u_diffuseTexture, fs_in.v_texCoords).rgb;
vec3 normal = normalize(fs_in.v_normal);
vec3 lightColor = vec3(1.0);
// ambient
vec3 ambient = 0.15 * color;
// diffuse
vec3 lightDir = normalize(u_lightPos - fs_in.v_fragPos);
float diff = max(dot(lightDir, normal), 0.0);
vec3 diffuse = diff * lightColor;
// specular
vec3 viewDir = normalize(u_viewPos - fs_in.v_fragPos);
float spec = 0.0;
vec3 halfWayDir = normalize(lightDir + viewDir);
spec = pow(max(dot(normal, halfWayDir), 0.0), 64.0);
vec3 specular = spec * lightColor;
// calculate shadow
float shadow = shadowCalculation(fs_in.v_fragPosLightSpace, normal, lightDir);
vec3 lighting = (ambient + (1.0 - shadow) * (diffuse + specular)) * color;
fragColor = vec4(lighting, 1.0);
}
What I'm really confused about is that the program runs when I'm using my local files. But when I pull the files from the Perforce repository and try and run it, then it throws the exception. I checked and all the necessary files are uploaded to Perforce. It would seem that there is something going wrong with which attributes are actually active? I'm not sure. Just scratching my head here...

Answer 1

glBindVertexArray(0);
glDisableVertexAttibArray(a_normalAttribLocation);
glDisableVertexAttribArray modifies the current VAO. You just removed the current VAO, setting it to 0. Which, in a core profile, means no VAO at all. In the compatibility profile, there is a VAO 0, which is probably why it works elsewhere: you're getting the compatibility profile on a different machine.
However, if you're using VAOs, it's not clear why you want to disable an attribute array at all. The whole point of VAOs is that you don't have to call the attribute array functions every frame. You just bind the VAO and go.