c++ - OpenGL – Severe distortions even with correct matrices -

my simple opengl program displaying severely distorted shape. i'm using glm matrix math. compared modelview matrix , projection matrix values program displaying values correctly. yet, still distorted. cause? here matrix code:

modelviewmatrix = glm::lookat(glm::vec3(3.0f, 5.0f, 7.0f), glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 1.0f, 0.0f));  projectionmatrix = glm::perspective(glm::radians(45.0f), (float)height/(float)width, 0.01f, 100.0f); 

and here vertex shader code:

#version 300 es  in mediump vec3 vertexposition; uniform mediump mat4 modelviewmatrix; uniform mediump mat4 projectionmatrix;  out vec3 finalposition;  void main(void) {  gl_position = projectionmatrix * modelviewmatrix * vec4(vertexposition, 1.0);  } 

here screenshots of (unlit) cuboid:

note correct image black one. both using exact same shader , same model view , projection matrix numbers. why happening?

i believe aspect ratio being calculated incorrectly - should width / height.

you have:

projectionmatrix = glm::perspective(glm::radians(45.0f),                     (float)height/(float)width, 0.01f, 100.0f); 

try replacing with:

projectionmatrix = glm::perspective(glm::radians(45.0f),                     (float)width/(float)height, 0.01f, 100.0f);