[vlc-devel] [PATCH 07/16] opengl: pass the viewpoint zoom/field of view with the yaw/pitch/roll

[Thomas Guillem]

From: Steve Lhomme <robux4 at videolabs.io>

Signed-off-by: Thomas Guillem <thomas at gllm.fr>
---
 modules/video_output/opengl.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/modules/video_output/opengl.c b/modules/video_output/opengl.c
index b117455..43c2cf5 100644
--- a/modules/video_output/opengl.c
+++ b/modules/video_output/opengl.c
@@ -207,6 +207,7 @@ struct vout_display_opengl_t {
     float f_teta;
     float f_phi;
     float f_roll;
+    float f_fov;
     float f_zoom;
 };
 
@@ -425,11 +426,19 @@ 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)
+SetViewpoint(vout_display_opengl_t *vgl, float f_teta, float f_phi, float f_roll,
+             float f_fov, float f_zoom)
 {
+    if (f_fov + 1.14f > (float) M_PI -0.001f)
+        return VLC_EBADVAR;
+    if (f_fov + 1.14f < 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 + 1.14f;
+    vgl->f_zoom = f_zoom;
+
     return VLC_SUCCESS;
 }
 
@@ -705,7 +714,8 @@ vout_display_opengl_t *vout_display_opengl_New(video_format_t *fmt,
     {
         SetViewpoint(vgl, vgl->fmt.f_pose_yaw_degrees   / 180.f * (float) M_PI,
                      vgl->fmt.f_pose_pitch_degrees / 180.f * (float) M_PI,
-                     vgl->fmt.f_pose_roll_degrees  / 180.f * (float) M_PI);
+                     vgl->fmt.f_pose_roll_degrees  / 180.f * (float) M_PI,
+                     0.f, 0.f);
     }
 
     /* */
@@ -792,7 +802,9 @@ int vout_display_opengl_SetViewpoint(vout_display_opengl_t *vgl, const vlc_viewp
 {
     return SetViewpoint(vgl, p_viewpoint->yaw / (float) VLC_VIEWPOINT_RADIAN_UNIT,
                         p_viewpoint->pitch / (float) VLC_VIEWPOINT_RADIAN_UNIT,
-                        p_viewpoint->roll / (float) VLC_VIEWPOINT_RADIAN_UNIT);
+                        p_viewpoint->roll / (float) VLC_VIEWPOINT_RADIAN_UNIT,
+                        p_viewpoint->fov / (float) VLC_VIEWPOINT_RADIAN_UNIT,
+                        p_viewpoint->zoom / (float) VLC_VIEWPOINT_RADIAN_UNIT);
 }
 
 picture_pool_t *vout_display_opengl_GetPool(vout_display_opengl_t *vgl, unsigned requested_count)
@@ -1101,14 +1113,11 @@ static void getZoomMatrix(float zoom, GLfloat matrix[static 16]) {
 }
 
 /* perspective matrix see https://www.opengl.org/sdk/docs/man2/xhtml/gluPerspective.xml */
-static void getProjectionMatrix(float sar, GLfloat matrix[static 16]) {
+static void getProjectionMatrix(float sar, float fovy, GLfloat matrix[static 16]) {
 
     float zFar  = 1000;
     float zNear = 0.01;
 
-    float fovy = (float) M_PI / 3;
-    float d = 1 / tan(fovy / 2);
-
     if (fovy > (float) M_PI -0.001)
         fovy = (float) M_PI -0.001;
 
@@ -1568,7 +1577,7 @@ static void DrawWithShaders(vout_display_opengl_t *vgl,
         || vgl->fmt.projection_mode == PROJECTION_MODE_CUBEMAP_LAYOUT_STANDARD)
     {
         float sar = (float) vgl->fmt.i_visible_width / vgl->fmt.i_visible_height;
-        getProjectionMatrix(sar, projectionMatrix);
+        getProjectionMatrix(sar, vgl->f_fov, projectionMatrix);
         getYRotMatrix(vgl->f_teta, yRotMatrix);
         getXRotMatrix(vgl->f_phi, xRotMatrix);
         getZRotMatrix(vgl->f_roll, zRotMatrix);
-- 
2.9.3