void ohmd_calc_default_proj_matrices(ohmd_device_properties* props)
{
mat4x4f proj_base; // base projection matrix
// Calculate where the lens is on each screen,
// and with the given value offset the projection matrix.
float screen_center = props->hsize / 4.0f;
float lens_shift = screen_center - props->lens_sep / 2.0f;
float proj_offset = 4.0f * lens_shift / props->hsize;
// Setup the base projection matrix. Each eye mostly have the
// same projection matrix with the exception of the offset.
omat4x4f_init_perspective(&proj_base, props->fov, props->ratio, props->znear, props->zfar);
// Setup the two adjusted projection matricies. Each is setup to deal
// with the fact that the lens is not in the center of the screen.
// These matrices only change of the hardware changes, so static.
mat4x4f translate;
omat4x4f_init_translate(&translate, proj_offset, 0, 0);
omat4x4f_mult(&translate, &proj_base, &props->proj_left);
omat4x4f_init_translate(&translate, -proj_offset, 0, 0);
omat4x4f_mult(&translate, &proj_base, &props->proj_right);
}
static void calc_derived_values(rift_priv *priv)
{
priv->base.properties.hsize = priv->display_info.h_screen_size;
priv->base.properties.vsize = priv->display_info.v_screen_size;
priv->base.properties.hres = priv->display_info.h_resolution;
priv->base.properties.vres = priv->display_info.v_resolution;
priv->base.properties.lens_sep = priv->display_info.lens_separation;
priv->base.properties.lens_vpos = priv->display_info.v_center;
priv->base.properties.fov = DEG_TO_RAD(125.5144f); // TODO calculate.
// Calculate the screen ratio of each subscreen.
float full_ratio = (float)priv->display_info.h_resolution /
(float)priv->display_info.v_resolution;
float ratio = full_ratio / 2.0f;
priv->base.properties.ratio = ratio;
// Calculate where the lens is on each screen,
// and with the given value offset the projection matrix.
float screen_center = priv->display_info.h_screen_size / 4.0f;
float lens_shift = screen_center - priv->display_info.lens_separation / 2.0f;
float proj_offset = 4.0f * lens_shift / priv->display_info.h_screen_size;
priv->calc_values.proj_offset = proj_offset;
// Setup the base projection matrix. Each eye mostly have the
// same projection matrix with the exception of the offset.
omat4x4f_init_perspective(&priv->calc_values.proj_base,
priv->base.properties.fov,
priv->base.properties.ratio,
priv->base.properties.znear,
priv->base.properties.zfar);
// Setup the two adjusted projection matricies. Each is setup to deal
// with the fact that the lens is not in the center of the screen.
// These matrices only change of the hardware changes, so static.
mat4x4f translate;
omat4x4f_init_translate(&translate, proj_offset, 0, 0);
omat4x4f_mult(&translate,
&priv->calc_values.proj_base,
&priv->base.properties.proj_left);
omat4x4f_init_translate(&translate, -proj_offset, 0, 0);
omat4x4f_mult(&translate,
&priv->calc_values.proj_base,
&priv->base.properties.proj_right);
}
int OHMD_APIENTRY ohmd_device_getf(ohmd_device* device, ohmd_float_value type, float* out)
{
switch(type){
case OHMD_LEFT_EYE_GL_MODELVIEW_MATRIX: {
vec3f point = {{0, 0, 0}};
quatf rot;
device->getf(device, OHMD_ROTATION_QUAT, (float*)&rot);
quatf tmp = device->rotation_correction;
oquatf_mult_me(&tmp, &rot);
rot = tmp;
mat4x4f orient, world_shift, result;
omat4x4f_init_look_at(&orient, &rot, &point);
omat4x4f_init_translate(&world_shift, +(device->properties.ipd / 2.0f), 0, 0);
omat4x4f_mult(&world_shift, &orient, &result);
omat4x4f_transpose(&result, (mat4x4f*)out);
return OHMD_S_OK;
}
case OHMD_RIGHT_EYE_GL_MODELVIEW_MATRIX: {
vec3f point = {{0, 0, 0}};
quatf rot;
device->getf(device, OHMD_ROTATION_QUAT, (float*)&rot);
oquatf_mult_me(&rot, &device->rotation_correction);
mat4x4f orient, world_shift, result;
omat4x4f_init_look_at(&orient, &rot, &point);
omat4x4f_init_translate(&world_shift, -(device->properties.ipd / 2.0f), 0, 0);
omat4x4f_mult(&world_shift, &orient, &result);
omat4x4f_transpose(&result, (mat4x4f*)out);
return OHMD_S_OK;
}
case OHMD_LEFT_EYE_GL_PROJECTION_MATRIX:
omat4x4f_transpose(&device->properties.proj_left, (mat4x4f*)out);
return OHMD_S_OK;
case OHMD_RIGHT_EYE_GL_PROJECTION_MATRIX:
omat4x4f_transpose(&device->properties.proj_right, (mat4x4f*)out);
return OHMD_S_OK;
case OHMD_SCREEN_HORIZONTAL_SIZE:
*out = device->properties.hsize;
return OHMD_S_OK;
case OHMD_SCREEN_VERTICAL_SIZE:
*out = device->properties.vsize;
return OHMD_S_OK;
case OHMD_LENS_HORIZONTAL_SEPARATION:
*out = device->properties.lens_sep;
return OHMD_S_OK;
case OHMD_LENS_VERTICAL_POSITION:
*out = device->properties.lens_vpos;
return OHMD_S_OK;
case OHMD_RIGHT_EYE_FOV:
case OHMD_LEFT_EYE_FOV:
*out = device->properties.fov;
return OHMD_S_OK;
case OHMD_RIGHT_EYE_ASPECT_RATIO:
case OHMD_LEFT_EYE_ASPECT_RATIO:
*out = device->properties.ratio;
return OHMD_S_OK;
case OHMD_EYE_IPD:
*out = device->properties.ipd;
return OHMD_S_OK;
case OHMD_PROJECTION_ZFAR:
*out = device->properties.zfar;
return OHMD_S_OK;
case OHMD_PROJECTION_ZNEAR:
*out = device->properties.znear;
return OHMD_S_OK;
case OHMD_ROTATION_QUAT:
{
int ret = device->getf(device, OHMD_ROTATION_QUAT, out);
if(ret != 0)
return ret;
oquatf_mult_me((quatf*)out, &device->rotation_correction);
quatf tmp = device->rotation_correction;
oquatf_mult_me(&tmp, (quatf*)out);
*(quatf*)out = tmp;
return OHMD_S_OK;
}
case OHMD_POSITION_VECTOR:
{
int ret = device->getf(device, OHMD_POSITION_VECTOR, out);
if(ret != 0)
return ret;
for(int i = 0; i < 3; i++)
out[i] += device->position_correction.arr[i];
return OHMD_S_OK;
}
default:
return device->getf(device, type, out);
}
}
int OHMD_APIENTRY ohmd_device_getf(ohmd_device* device, ohmd_float_value type, float* out)
{
switch(type){
case OHMD_LEFT_EYE_GL_MODELVIEW_MATRIX: {
vec3f point = {{0, 0, 0}};
quatf rot;
device->getf(device, OHMD_ROTATION_QUAT, (float*)&rot);
mat4x4f orient, world_shift, result;
omat4x4f_init_look_at(&orient, &rot, &point);
omat4x4f_init_translate(&world_shift, +(device->properties.ipd / 2.0f), 0, 0);
omat4x4f_mult(&world_shift, &orient, &result);
omat4x4f_transpose(&result, (mat4x4f*)out);
return 0;
}
case OHMD_RIGHT_EYE_GL_MODELVIEW_MATRIX: {
vec3f point = {{0, 0, 0}};
quatf rot;
device->getf(device, OHMD_ROTATION_QUAT, (float*)&rot);
mat4x4f orient, world_shift, result;
omat4x4f_init_look_at(&orient, &rot, &point);
omat4x4f_init_translate(&world_shift, -(device->properties.ipd / 2.0f), 0, 0);
omat4x4f_mult(&world_shift, &orient, &result);
omat4x4f_transpose(&result, (mat4x4f*)out);
return 0;
}
case OHMD_LEFT_EYE_GL_PROJECTION_MATRIX:
omat4x4f_transpose(&device->properties.proj_left, (mat4x4f*)out);
return 0;
case OHMD_RIGHT_EYE_GL_PROJECTION_MATRIX:
omat4x4f_transpose(&device->properties.proj_right, (mat4x4f*)out);
return 0;
case OHMD_SCREEN_HORIZONTAL_SIZE:
*out = device->properties.hsize;
return 0;
case OHMD_SCREEN_VERTICAL_SIZE:
*out = device->properties.vsize;
return 0;
case OHMD_LENS_HORIZONTAL_SEPARATION:
*out = device->properties.lens_sep;
return 0;
case OHMD_LENS_VERTICAL_POSITION:
*out = device->properties.lens_vpos;
return 0;
case OHMD_RIGHT_EYE_FOV:
case OHMD_LEFT_EYE_FOV:
*out = device->properties.fov;
return 0;
case OHMD_RIGHT_EYE_ASPECT_RATIO:
case OHMD_LEFT_EYE_ASPECT_RATIO:
*out = device->properties.ratio;
return 0;
case OHMD_EYE_IPD:
*out = device->properties.ipd;
return 0;
case OHMD_PROJECTION_ZFAR:
*out = device->properties.zfar;
return 0;
case OHMD_PROJECTION_ZNEAR:
*out = device->properties.znear;
return 0;
default:
return device->getf(device, type, out);
}
}
