[vlc-devel] [PATCH 09/17] opengl: handle the viewpoint changes when rendering

[Steve Lhomme]

--
replaces https://patches.videolan.org/patch/14910/
* squashed with https://patches.videolan.org/patch/14910/
* use M_PI as a float to avoid double math

replaces https://patches.videolan.org/patch/14960/
* use vout_viewpoint_t with float values rather than integers

replaces https://patches.videolan.org/patch/14975/
* use macros to simplify degree/radians conversions
---
 modules/video_output/opengl.c | 41 ++++++++++++++++++++++++++++++++++++-----
 modules/video_output/opengl.h |  3 +++
 2 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/modules/video_output/opengl.c b/modules/video_output/opengl.c
index 16c6592..348a52c 100644
--- a/modules/video_output/opengl.c
+++ b/modules/video_output/opengl.c
@@ -424,6 +424,27 @@ static void BuildXYZFragmentShader(vout_display_opengl_t *vgl,
 
 #endif
 
+static int
+SetViewpoint(vout_display_opengl_t *vgl, float f_teta, float f_phi, float f_roll,
+             float f_fov, float f_zoom)
+{
+    if (f_fov > (float) M_PI -0.001f)
+        return VLC_EBADVAR;
+    if (f_fov < 0.001f)
+        return VLC_EBADVAR;
+    vgl->f_teta = f_teta - (float) M_PI / 2;
+    vgl->f_phi  = f_phi;
+    vgl->f_roll = f_roll;
+    vgl->f_fov  = f_fov;
+    vgl->f_zoom = f_zoom;
+
+    return VLC_SUCCESS;
+}
+
+#define FROM_RADIANS(d)  (d * 180.f / (float) M_PI)
+#define TO_RADIANS(d)    (d * (float) M_PI / 180.f)
+#define MILLI_TO_RADIANS(vdg)    TO_RADIANS(FROM_MILLI_INT(vdg))
+
 vout_display_opengl_t *vout_display_opengl_New(video_format_t *fmt,
                                                const vlc_fourcc_t **subpicture_chromas,
                                                vlc_gl_t *gl)
@@ -694,11 +715,11 @@ vout_display_opengl_t *vout_display_opengl_New(video_format_t *fmt,
     if (vgl->fmt.projection_mode == PROJECTION_MODE_EQUIRECTANGULAR
         || vgl->fmt.projection_mode == PROJECTION_MODE_CUBEMAP_LAYOUT_STANDARD)
     {
-        vgl->f_teta = vgl->fmt.f_pose_yaw_degrees   / 180. * (float) M_PI;
-        vgl->f_phi  = vgl->fmt.f_pose_pitch_degrees / 180. * (float) M_PI;
-        vgl->f_roll = vgl->fmt.f_pose_roll_degrees  / 180. * (float) M_PI;
-        vgl->f_fov  = vgl->fmt.f_pose_fov_degrees   / 180. * (float) M_PI;
-        vgl->f_teta -= (float) M_PI/2;
+        SetViewpoint(vgl, TO_RADIANS(vgl->fmt.f_pose_yaw_degrees),
+                          TO_RADIANS(vgl->fmt.f_pose_pitch_degrees),
+                          TO_RADIANS(vgl->fmt.f_pose_roll_degrees),
+                          TO_RADIANS(vgl->fmt.f_pose_fov_degrees),
+                          0.f);
     }
 
     /* */
@@ -781,6 +802,16 @@ void vout_display_opengl_Delete(vout_display_opengl_t *vgl)
     free(vgl);
 }
 
+int vout_display_opengl_SetViewpoint(vout_display_opengl_t *vgl,
+                                     const vlc_viewpoint_t *p_viewpoint)
+{
+    return SetViewpoint(vgl, MILLI_TO_RADIANS(p_viewpoint->yaw),
+                             MILLI_TO_RADIANS(p_viewpoint->pitch),
+                             MILLI_TO_RADIANS(p_viewpoint->roll),
+                             MILLI_TO_RADIANS(p_viewpoint->fov),
+                             FROM_MILLI_INT(p_viewpoint->zoom));
+}
+
 picture_pool_t *vout_display_opengl_GetPool(vout_display_opengl_t *vgl, unsigned requested_count)
 {
     if (vgl->pool)
diff --git a/modules/video_output/opengl.h b/modules/video_output/opengl.h
index 4ae9400..ff76902 100644
--- a/modules/video_output/opengl.h
+++ b/modules/video_output/opengl.h
@@ -32,6 +32,7 @@
 #include <vlc_common.h>
 #include <vlc_picture_pool.h>
 #include <vlc_opengl.h>
+#include <vlc_vout.h>
 
 /* Change USE_OPENGL_ES value to set the OpenGL ES version (1, 2) you want to use
  * A value of 0 will activate normal OpenGL */
@@ -96,6 +97,8 @@ void vout_display_opengl_Delete(vout_display_opengl_t *vgl);
 
 picture_pool_t *vout_display_opengl_GetPool(vout_display_opengl_t *vgl, unsigned);
 
+int vout_display_opengl_SetViewpoint(vout_display_opengl_t *vgl, const vlc_viewpoint_t*);
+
 int vout_display_opengl_Prepare(vout_display_opengl_t *vgl,
                                 picture_t *picture, subpicture_t *subpicture);
 int vout_display_opengl_Display(vout_display_opengl_t *vgl,
-- 
2.10.1