glm-math

How do I convert a glm::vec4 to a glm::vec3 ? Only x , y , z is required- the w component can be dropped. In GLSL this can be done with .xyz [1], but in glm this results in a compile error: error: 'glm::vec4' has no member named 'xyz' [1] http://en.wikibooks.org/wiki/GLSL_Programming/Vector_and_Matrix_Operations#Components Just use vec3 constructor . Here, on 0.9.5 branch: glm::vec4 v4(1, 2, 3, 4); glm::vec3 v(v4); printf("%s\n", glm::to_string(v).c_str()); and gives this output fvec3(1.000000, 2.000000, 3.000000) SystemParadox Swizzling is not enabled by default in glm as it uses macros which

How to create a billboard translation matrix from a point in space using glm? Just set the upper left 3×3 submatrix of the transformation to identity. Update: Fixed function OpenGL variant: void makebillboard_mat4x4(double *BM, double const * const MV) { for(size_t i = 0; i < 3; i++) { for(size_t j = 0; j < 3; j++) { BM[4*i + j] = i==j ? 1 : 0; } BM[4*i + 3] = MV[4*i + 3]; } for(size_t i = 0; i < 4; i++) { BM[12 + i] = MV[12 + i]; } } void mygltoolMakeMVBillboard(void) { GLenum active_matrix; double MV[16]; glGetIntegerv(GL_MATRIX_MODE, &active_matrix); glMatrixMode(GL_MODELVIEW); glGetDoublev

I am currently trying to port my OpenGL application to Android and am stuck on how to import and build GLM http://glm.g-truc.net/ properly. I have no trouble using GLM in standard C++ apps, however I am pretty new to the NDK. I have tried all other solutions posted around the web with no luck. Here is what I have so far: I am using the latest version of GLM (0.9.4) My .cpp file contains: #include <glm\glm.hpp> My Android.mk file looks like: LOCAL_PATH:= $(call my-dir) include $(CLEAR_VARS) LOCAL_MODULE := libgl2jni LOCAL_CFLAGS := -Werror LOCAL_SRC_FILES := gl_code.cpp LOCAL_LDLIBS := -llog

NDC coordinates for OpenGL form a cube, who's -Z side presses against the screen while it's +Z side is farthest away. When I use... // ortho arguments are: left, right, bottom, top, near, far pos = pos * glm::ortho<float>(-1, 1, -1, 1, -1, 1); ...the z component of pos is reflected; -1 becomes 1, 10 becomes -10, etc. glm::persp does a similar thing and it's kind of a weird? If a position has a z equal to near , I would expect it to rest on the screen facing plane of the NDC cube, but instead it's sign is flipped arbitrarily; it doesn't even land on the farthest facing side. Why is this? NDC

Currently using VC++ 11 with SDL2, GLM, and GLEW. The issue is stemming from GLM when I attempt to do two things: Create a rotation matrix, create a perspective camera matrix (3D). The error is: "GLM: perspective function taking degrees as a parameter is deprecated" despite the fact that I am passing radians (as floats) to both functions. It says I should define something like "#define GLM_FORCE_RADIANS." Is that really necessary? Personally I use degrees for everything, but OpenGL, so having to convert back and forth (for AI movement and what not) is a pain and actually causes a spike in CPU

I'm working on a FPS style camera to fly around my 3D scene using OpenGL. I'm using GLM for the mathmetics and I calculate a direction vector with a glm::rotate on the x-axis and the y-axis using mouse movements. I have a static up vector since I'm fine with strafing on the horizontal axis and don't really need any rolls. However, when I move forward towards the negative z direction and I eventually reach the center point of the scene (z=0) the vertical camera flips (y direction). Moving the mouse downwards will now result in an upward motion. The direction vectors are calculated like they

What are the necessary maths to achieve the camera panning effect that's used in 3ds max? In 3ds max the distance between the cursor and the mesh will always remain the same throughout the entire movement (mouse_down+mouse_motion+mouse_up). My naive and failed attempt has been trying to move the camera on the plane XY by using dt (frame time) multiplied by some hardcoded constant and the result is really ugly and uintuitive. The code I've got so far is: def glut_mouse(self, button, state, x, y): self.last_mouse_pos = vec2(x, y) self.mouse_down_pos = vec2(x, y) def glut_motion(self, x, y): pos