Rewrite greyscale OpenGL system to use GLSL

Add ability to blend color and greyscale based on window alpha (actual window alpha currently set at 0.5 when blending is enabled)
Reenable greyscale logout effect when compositor is in use

1 files changed, 29 insertions, 2 deletions

diff --git a/twin/compton-tde/common.h b/twin/compton-tde/common.h
index 759e64698..9ff5a2148 100644
--- a/twin/compton-tde/common.h
+++ b/twin/compton-tde/common.h
@@ -490,6 +490,21 @@ typedef struct {
 } glx_blur_cache_t;
 
 typedef struct {
+  /// Fragment shader for greyscale.
+  GLuint frag_shader;
+  /// GLSL program for greyscale.
+  GLuint prog;
+  /// Location of uniform "greyscale_weights" in greyscale GLSL program.
+  GLint unifm_greyscale_weights;
+  /// Location of uniform "enable_blend" in greyscale GLSL program.
+  GLint unifm_enable_blend;
+  /// Location of uniform "tex_scr" in greyscale GLSL program.
+  GLint unifm_tex_scr;
+  /// Location of uniform "alpha_scr" in greyscale GLSL program.
+  GLint unifm_alpha_scr;
+} glx_greyscale_t;
+
+typedef struct {
   /// Framebuffer used for greyscale conversion.
   GLuint fbo;
   /// Textures used for greyscale conversion.
@@ -817,6 +832,9 @@ typedef struct {
 #ifdef CONFIG_VSYNC_OPENGL_GLSL
   glx_blur_pass_t blur_passes[MAX_BLUR_PASS];
 #endif
+#ifdef CONFIG_VSYNC_OPENGL_GLSL
+  glx_greyscale_t greyscale_glsl;
+#endif
 } glx_session_t;
 
 #define CGLX_SESSION_INIT { .context = NULL }
@@ -1068,6 +1086,8 @@ typedef struct _session_t {
   Atom atom_win_type_tde_transparent_to_desktop;
   /// Atom of property <code>_TDE_TRANSPARENCY_FILTER_GREYSCALE</code>.
   Atom atom_win_type_tde_transparency_filter_greyscale;
+  /// Atom of property <code>_TDE_TRANSPARENCY_FILTER_GREYSCALE_BLEND</code>.
+  Atom atom_win_type_tde_transparency_filter_greyscale_blend;
   /// Array of atoms of all possible window types.
   Atom atoms_wintypes[NUM_WINTYPES];
   /// Linked list of additional atoms to track.
@@ -1263,6 +1283,11 @@ typedef struct _win {
   /// Background state on last paint.
   bool greyscale_background_last;
 
+  /// Whether to set window background to blended greyscale.
+  bool greyscale_blended_background;
+  /// Blended greyscale alpha divisor.
+  int greyscale_blended_background_alpha_divisor;
+
   /// Whether to show black background
   bool show_black_background;
 
@@ -2202,6 +2227,9 @@ glx_on_root_change(session_t *ps);
 bool
 glx_init_blur(session_t *ps);
 
+bool
+glx_init_greyscale(session_t *ps);
+
 #ifdef CONFIG_VSYNC_OPENGL_GLSL
 bool
 glx_load_prog_main(session_t *ps,
@@ -2245,7 +2273,7 @@ glx_dim_dst(session_t *ps, int dx, int dy, int width, int height, float z,
 
 bool
 glx_greyscale_dst(session_t *ps, int dx, int dy, int width, int height, float z,
-    XserverRegion reg_tgt, const reg_data_t *pcache_reg, glx_greyscale_cache_t *pbc);
+    glx_texture_t *ptex, XserverRegion reg_tgt, const reg_data_t *pcache_reg, glx_greyscale_cache_t *pbc);
 
 bool
 glx_render_(session_t *ps, const glx_texture_t *ptex,
@@ -2342,7 +2370,6 @@ free_glx_bc(session_t *ps, glx_blur_cache_t *pbc) {
 static inline void
 free_glx_gc_resize(session_t *ps, glx_greyscale_cache_t *pbc) {
   free_texture_r(ps, &pbc->textures[0]);
-  free_texture_r(ps, &pbc->textures[1]);
   pbc->width = 0;
   pbc->height = 0;
 }