I'm trying to tranlate a matrix by xy but the result is strange. can someone help me translate and rotate the matrix properly?

void Transform_Update(Transform *transform, GLfloat depth)
    Matrix4_Set(transform->transformationMatrix, 0, 3, transform->position->x);
    Matrix4_Set(transform->transformationMatrix, 1, 3, transform->position->y);
    Matrix4_Set(transform->transformationMatrix, 2, 3, depth);

Here is my Matrix set value.

void Matrix4_Set(Matrix4 *m, GLuint line, GLuint column, GLfloat value)
    m->data[line * 4 + column] = value;

Here is where I make the matrix to the identity matrix

void Matrix4_SetToIdentity(Matrix4 *m)
    GLfloat data[16] = { 1, 0, 0, 0,
                         0, 1, 0, 0,
                         0, 0, 1, 0,
                         0, 0, 0, 1 };

    memcpy(m->data, data, sizeof(GLfloat) * 16 );

This is where I render my mesh and update shader values

void Renderer_Render(Renderer *renderer, Camera *camera)

    Transform_Update(renderer->gameObject->transform, renderer->depth);

    GLint location = Shader_GetUniformLocation(renderer->shader, "transformationMatrix");
    glProgramUniformMatrix4fv(renderer->shader->id, location, 1, GL_FALSE, renderer->gameObject->transform->transformationMatrix->data);

    GLint location2 = Shader_GetUniformLocation(renderer->shader, "projectionMatrix");
    glProgramUniformMatrix4fv(renderer->shader->id, location2, 1, GL_FALSE, camera->projectionMatrix);

    GLint location3 = Shader_GetUniformLocation(renderer->shader, "viewMatrix");
    glProgramUniformMatrix4fv(renderer->shader->id, location3, 1, GL_FALSE, camera->viewMatrix);

    glBindTexture(GL_TEXTURE_2D, renderer->texture->id);


Here is my shader transforming the vertices :

#version 400 core

in vec3 position;
in vec2 textureCoords;

out vec2 pass_textureCoords;

uniform mat4 transformationMatrix;
uniform mat4 projectionMatrix;
uniform mat4 viewMatrix;

void main(void) { 

    vec4 worldPosition = transformationMatrix * vec4(position, 1.0);
    vec4 positionRelativeToCamera = viewMatrix * worldPosition;

    gl_Position = projectionMatrix * positionRelativeToCamera;
    pass_textureCoords = textureCoords;

Here is how I get the view and projection matrix :

void Camera_Render(Screen *screen, Camera *camera)
    glClearColor(camera->backgroundColor->red, camera->backgroundColor->green, camera->backgroundColor->blue, camera->backgroundColor->alpha);

    glTranslatef(camera->transform->position->x, camera->transform->position->y, 0);
    glRotatef(camera->transform->angle, 0, 0, 1);

    glGetFloatv(GL_PROJECTION_MATRIX, camera->projectionMatrix);
    glGetFloatv(GL_MODELVIEW_MATRIX, camera->viewMatrix);

The current output when I change X is this :

The output seams to rotate...Not really...it's just wierd


It looks like your matrices are row-major, whereas OpenGL expects column-major matrices. In your calls to glProgramUniformMatrix4fv(), you should set the transpose parameter to GL_TRUE, like this:

glProgramUniformMatrix4fv(renderer->shader->id, location, 1, GL_TRUE, renderer->gameObject->transform->transformationMatrix->data);
  • \$\begingroup\$ bump…. I've changed it but now nothing is rendered. Do you know what is the problem? \$\endgroup\$ – David Neves Dec 2 '18 at 4:15
  • \$\begingroup\$ Great! If you found it useful, don't forget to mark it as having solved your problem by clicking the green checkmark to the left. \$\endgroup\$ – user1118321 Dec 3 '18 at 0:49

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