Modern OpenGL GLSL Camera

GLSL Newbie · 2018-02-15T20:46:54

Hi All, I'm reading the tutorials from learnOpengl site (nice site) and I'm having a question on the camera (https://learnopengl.com/Getting-started/Camera). I always saw the camera being manipulated with the lookat, but in tutorial I saw the camera being changed through the MVP arrays, which do not seem to be camera, but rather the scene that changes: Vertex Shader: #version 330 core layout (location = 0) in vec3 aPos; layout (location = 1) in vec2 aTexCoord; out vec2 TexCoord; uniform mat4 model; uniform mat4 view; uniform mat4 projection; void main() { gl_Position = projection * view * model * vec4(aPos, 1.0f); TexCoord = vec2(aTexCoord.x, aTexCoord.y); } then, the matrix manipulated: ..... glm::mat4 projection = glm::perspective(glm::radians(fov), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f); ourShader.setMat4("projection", projection); .... glm::mat4 view = glm::lookAt(cameraPos, cameraPos + cameraFront, cameraUp); ourShader.setMat4("view", view); .... model = glm::rotate(model, glm::radians(angle), glm::vec3(1.0f, 0.3f, 0.5f)); ourShader.setMat4("model", model); So, some doubts: - Why use it like that? - Is it okay to manipulate the camera that way? -in this way, are not the vertex's positions that changes instead of the camera? - I need to pass MVP to all shaders of object in my scenes ? What it seems, is that the camera stands still and the scenery that changes... it's right? Thank you

For Beginners OpenGL

Started by RenanRR February 14, 2018 11:34 PM

10 comments, last by RenanRR 6 years, 9 months ago

RenanRR

Author

107

February 15, 2018 08:46 PM

2 minutes ago, swiftcoder said:

Shaarigan is being a bit... overly reductive. It's perfectly idiomatic to call the thing that manages the View+Projection matrices a "camera".

hahahaha, ok. Understood.

My english is rusty.

Thank You (For Now)...