Render wallpaper

6 files changed, 239 insertions, 18 deletions

diff --git a/build.sh b/build.sh
index 4ae804d..b749f9f 100755
--- a/build.sh
+++ b/build.sh
@@ -13,5 +13,6 @@ includes="$(pkg-config --cflags $dependencies)"
 mkdir -p build
 $CC -c src/compositor.c -o build/compositor.o $opts $includes
 $CC -c src/window_texture.c -o build/window_texture.o $opts $includes
+$CC -c src/pixmap_texture.c -o build/pixmap_texture.o $opts $includes
 $CC -c src/main.c -o build/main.o $opts $includes
 $CC build/*.o -o ngxc $opts $libs
diff --git a/src/compositor.c b/src/compositor.c
index 1e75d77..994404e 100644
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -1,9 +1,14 @@
 #include "compositor.h"
+
 #include <string.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <time.h>
 
+#include <X11/Xatom.h>
+
+/* TODO: Handle wallpaper change and update on root window resize */
+
 static double clock_get_monotonic_seconds(void) {
     struct timespec ts;
     ts.tv_sec = 0;
@@ -24,15 +29,50 @@ static ngxc_window* ngxc_compositor_get_window_by_id(ngxc_compositor *self, Wind
     return NULL;
 }
 
+static Pixmap x11_wallpaper_get_pixmap(ngxc_compositor *self) {
+    const char *background_props[] = {
+        "_XROOTPMAP_ID",
+        "_XSETROOT_ID",
+        NULL
+    };
+
+    const Window root_window = DefaultRootWindow(self->dpy);
+    Pixmap wallpaper_pixmap = None;
+
+    for(int i = 0; background_props[i]; ++i) {
+        const Atom atom = XInternAtom(self->dpy, background_props[i], False);
+        Atom actual_type;
+        int actual_format;
+        unsigned long items_count;
+        unsigned long bytes_after;
+        unsigned char *prop = NULL;
+        if(XGetWindowProperty(self->dpy, root_window, atom, 0, 1, False, XA_PIXMAP, &actual_type, &actual_format, &items_count, &bytes_after, &prop) == Success && prop) {
+            wallpaper_pixmap = *(Pixmap*)prop;
+            XFree(prop);
+            break;
+        }
+
+        if(prop)
+            XFree(prop);
+    }
+
+    return wallpaper_pixmap;
+}
+
 void ngxc_compositor_init(ngxc_compositor *self, Display *dpy, Window composite_window) {
     memset(self, 0, sizeof(*self));
     self->dpy = dpy;
     self->composite_window = composite_window;
     self->frame_timer = clock_get_monotonic_seconds();
+
+    const Pixmap wallpaper_pixmap = x11_wallpaper_get_pixmap(self);
+    if(!ngxc_pixmap_texture_init(&self->wallpaper_texture, self->dpy, wallpaper_pixmap)) {
+        fprintf(stderr, "error: failed to create texture for wallpaper pixmap %ld\n", wallpaper_pixmap);
+    }
 }
 
 void ngxc_compositor_deinit(ngxc_compositor *self) {
-
+    /* TODO: Cleanup? */
 }
 
 void ngxc_compositor_add_window(ngxc_compositor *self, Window window) {
@@ -101,7 +141,7 @@ void ngxc_compositor_remove_window(ngxc_compositor *self, Window window) {
     }
 }
 
-static void render_texture(const ngxc_window *window) {
+static void render_texture(GLuint texture_id, int x, int y, int width, int height) {
     float matrix[16] = {
         1.0f, 0.0f, 0.0f, 0.0f,
         0.0f, 1.0f, 0.0f, 0.0f,
@@ -109,28 +149,28 @@ static void render_texture(const ngxc_window *window) {
         0.0f, 0.0f, 0.0f, 1.0f,
     };
 
-    matrix[0] = 1.0f / (float)window->texture.width;
-    matrix[5] = 1.0f / (float)window->texture.height;
+    matrix[0] = 1.0f / (float)width;
+    matrix[5] = 1.0f / (float)height;
 
     glMatrixMode(GL_TEXTURE);
     glLoadMatrixf(matrix);
     glMatrixMode(GL_MODELVIEW);
-    glBindTexture(GL_TEXTURE_2D, window->texture.texture_id);
+    glBindTexture(GL_TEXTURE_2D, texture_id);
 
     glColor4ub(255, 255, 255, 255);
-    //glTranslatef(window->x, window->y, 0.0f);
+    //glTranslatef(x, y, 0.0f);
     glBegin(GL_QUADS);
         glTexCoord2f(0.0f, 0.0f);
-        glVertex2f(window->x, window->y);
+        glVertex2f(x, y);
 
-        glTexCoord2f(window->texture.width, 0.0f);
-        glVertex2f(window->x + window->texture.width, window->y);
+        glTexCoord2f(width, 0.0f);
+        glVertex2f(x + width, y);
 
-        glTexCoord2f(window->texture.width, window->texture.height);
-        glVertex2f(window->x + window->texture.width, window->y + window->texture.height);
+        glTexCoord2f(width, height);
+        glVertex2f(x + width, y + height);
 
-        glTexCoord2f(0.0f, window->texture.height);
-        glVertex2f(window->x, window->y + window->texture.height);
+        glTexCoord2f(0.0f, height);
+        glVertex2f(x, y + height);
     glEnd();
     glLoadIdentity();
 
@@ -140,12 +180,16 @@ static void render_texture(const ngxc_window *window) {
 /* TODO: Skip windows that are not visible on the screen */
 /* TODO: Disable compositing for fullscreen windows, if that option is enabled */
 void ngxc_compositor_render(ngxc_compositor *self) {
-    glClearColor(1.0f, 0.0f, 0.0f, 1.0f);
+    glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
     glClear(GL_COLOR_BUFFER_BIT);
 
+    if(self->wallpaper_texture.texture_id > 0) {
+        render_texture(self->wallpaper_texture.texture_id, 0, 0, self->wallpaper_texture.width, self->wallpaper_texture.height);
+    }
+
     for(int i = 0; i < self->num_windows; ++i) {
         const ngxc_window *window_obj = &self->windows[i];
-        render_texture(window_obj);
+        render_texture(window_obj->texture.texture_id, window_obj->x, window_obj->y, window_obj->texture.width, window_obj->texture.height);
     }
 
     const double now = clock_get_monotonic_seconds();
diff --git a/src/compositor.h b/src/compositor.h
index cf520d5..f6db300 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -2,6 +2,7 @@
 #define NGXC_COMPOSITOR_H
 
 #include "window_texture.h"
+#include "pixmap_texture.h"
 
 // TODO: Make dynamic
 #define NGXC_COMPOSITOR_MAX_WINDOWS 100
@@ -16,6 +17,9 @@ typedef struct {
     Display *dpy;
     Window composite_window;
     double frame_timer;
+
+    ngxc_pixmap_texture wallpaper_texture;
+    
     ngxc_window windows[NGXC_COMPOSITOR_MAX_WINDOWS];
     int num_windows;
 } ngxc_compositor;
diff --git a/src/pixmap_texture.c b/src/pixmap_texture.c
new file mode 100644
index 0000000..b31b346
--- /dev/null
+++ b/src/pixmap_texture.c
@@ -0,0 +1,140 @@
+#include "pixmap_texture.h"
+
+#include <stdio.h>
+
+bool ngxc_pixmap_texture_init(ngxc_pixmap_texture *window_texture, Display *display, Pixmap pixmap) {
+    window_texture->display = display;
+    window_texture->pixmap = pixmap;
+    window_texture->glx_pixmap = None;
+    window_texture->texture_id = 0;
+    window_texture->width = 0;
+    window_texture->height = 0;
+    return ngxc_pixmap_texture_on_resize(window_texture);
+}
+
+static void ngxc_pixmap_texture_cleanup(ngxc_pixmap_texture *self, int delete_texture) {
+    if(delete_texture && self->texture_id) {
+        glDeleteTextures(1, &self->texture_id);
+        self->texture_id = 0;
+    }
+
+    if(self->glx_pixmap) {
+        glXDestroyPixmap(self->display, self->glx_pixmap);
+        glXReleaseTexImageEXT(self->display, self->glx_pixmap, GLX_FRONT_EXT);
+        self->glx_pixmap = None;
+    }
+}
+
+void ngxc_pixmap_texture_deinit(ngxc_pixmap_texture *self) {
+    ngxc_pixmap_texture_cleanup(self, 1);
+}
+
+bool ngxc_pixmap_texture_on_resize(ngxc_pixmap_texture *self) {
+    ngxc_pixmap_texture_cleanup(self, 0);
+
+    GLXFBConfig *configs = NULL;
+    GLXPixmap glx_pixmap = None;
+    GLuint texture_id = 0;
+    int glx_pixmap_bound = 0;
+
+    const int pixmap_config[] = {
+        GLX_BIND_TO_TEXTURE_RGB_EXT, True,
+        GLX_DRAWABLE_TYPE, GLX_PIXMAP_BIT | GLX_WINDOW_BIT,
+        GLX_BIND_TO_TEXTURE_TARGETS_EXT, GLX_TEXTURE_2D_BIT_EXT,
+        /*GLX_BIND_TO_MIPMAP_TEXTURE_EXT, True,*/
+        GLX_BUFFER_SIZE, 24,
+        GLX_RED_SIZE, 8,
+        GLX_GREEN_SIZE, 8,
+        GLX_BLUE_SIZE, 8,
+        GLX_ALPHA_SIZE, 0,
+        None
+    };
+
+    const int pixmap_attribs[] = {
+        GLX_TEXTURE_TARGET_EXT, GLX_TEXTURE_2D_EXT,
+        GLX_TEXTURE_FORMAT_EXT, GLX_TEXTURE_FORMAT_RGB_EXT,
+        /*GLX_MIPMAP_TEXTURE_EXT, True,*/
+        None
+    };
+
+    Window root_window;
+    int x, y;
+    unsigned int width = 0;
+    unsigned int height = 0;
+    unsigned int border_width;
+    unsigned int depth = 32;
+    if(!XGetGeometry(self->display, self->pixmap, &root_window, &x, &y, &width, &height, &border_width, &depth)) {
+        fprintf(stderr, "Failed to get pixmap attributes\n");
+        return false;
+    }
+
+    GLXFBConfig config;
+    int c;
+    configs = glXChooseFBConfig(self->display, 0, pixmap_config, &c);
+    if(!configs) {
+        fprintf(stderr, "Failed to choose fb config\n");
+        return false;
+    }
+
+    int found = 0;
+    for (int i = 0; i < c; i++) {
+        config = configs[i];
+        XVisualInfo *visual = glXGetVisualFromFBConfig(self->display, config);
+        if(!visual)
+            continue;
+
+        if((int)depth != visual->depth) {
+            XFree(visual);
+            continue;
+        }
+        XFree(visual);
+        found = 1;
+        break;
+    }
+
+    if(!found) {
+        fprintf(stderr, "No matching fb config found\n");
+        goto cleanup;
+    }
+
+    glx_pixmap = glXCreatePixmap(self->display, config, self->pixmap, pixmap_attribs);
+    if(!glx_pixmap) {
+        goto cleanup;
+    }
+
+    if(self->texture_id == 0) {
+        glGenTextures(1, &texture_id);
+        if(texture_id == 0) {
+            goto cleanup;
+        }
+        glBindTexture(GL_TEXTURE_2D, texture_id);
+    } else {
+        glBindTexture(GL_TEXTURE_2D, self->texture_id);
+    }
+
+    glXBindTexImageEXT(self->display, glx_pixmap, GLX_FRONT_EXT, NULL);
+    glx_pixmap_bound = 1;
+
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    self->width = width;
+    self->height = height;
+
+    XFree(configs);
+    self->glx_pixmap = glx_pixmap;
+    if(texture_id != 0)
+        self->texture_id = texture_id;
+    return true;
+
+    cleanup:
+    if(texture_id != 0)     glDeleteTextures(1, &texture_id);
+    if(glx_pixmap)          glXDestroyPixmap(self->display, glx_pixmap);
+    if(glx_pixmap_bound)    glXReleaseTexImageEXT(self->display, glx_pixmap, GLX_FRONT_EXT);
+    if(configs)             XFree(configs);
+    return false;
+}
diff --git a/src/pixmap_texture.h b/src/pixmap_texture.h
new file mode 100644
index 0000000..37f7ec4
--- /dev/null
+++ b/src/pixmap_texture.h
@@ -0,0 +1,28 @@
+#ifndef NGXC_PIXMAP_TEXTURE_H
+#define NGXC_PIXMAP_TEXTURE_H
+
+#include <stdbool.h>
+
+#define GLX_GLXEXT_PROTOTYPES
+#include <GL/glx.h>
+#include <GL/glxext.h>
+#include <X11/Xlib.h>
+
+typedef struct {
+    Display *display;
+    Pixmap pixmap;
+    GLXPixmap glx_pixmap;
+    GLuint texture_id;
+    int width;
+    int height;
+} ngxc_pixmap_texture;
+
+bool ngxc_pixmap_texture_init(ngxc_pixmap_texture *self, Display *display, Pixmap pixmap);
+void ngxc_pixmap_texture_deinit(ngxc_pixmap_texture *self);
+
+/*
+    This should ONLY be called when the pixmap is resized.
+*/
+bool ngxc_pixmap_texture_on_resize(ngxc_pixmap_texture *self);
+
+#endif /* NGXC_PIXMAP_TEXTURE_H */
diff --git a/src/window_texture.c b/src/window_texture.c
index c3bde72..bd4c558 100644
--- a/src/window_texture.c
+++ b/src/window_texture.c
@@ -1,7 +1,11 @@
 #include "window_texture.h"
-#include <X11/extensions/Xcomposite.h>
+
 #include <stdio.h>
 
+#include <X11/extensions/Xcomposite.h>
+
+/* TODO: Use pixmap_texture for window_texture */
+
 int window_texture_init(WindowTexture *window_texture, Display *display, Window window) {
     window_texture->display = display;
     window_texture->window = window;
@@ -137,8 +141,8 @@ int window_texture_on_resize(WindowTexture *self) {
 
     glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
     glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
-    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
-    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
  
     /*
     float fLargest = 0.0f;