xephyr: Build support for rendering with glamor using a -glamor option.

v2: Avoid making the Ximage for the screen that we'll never use, and
    drive the screen pixmap creation for glamor ourselves.

Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Keith Packard <keithp@keithp.com> (v1)
Reviewed-by: Adam Jackson <ajax@redhat.com>

1 files changed, 292 insertions, 0 deletions

diff --git a/hw/kdrive/ephyr/ephyr_glamor_glx.c b/hw/kdrive/ephyr/ephyr_glamor_glx.c
new file mode 100644
index 000000000..a937c1ac5
--- /dev/null
+++ b/hw/kdrive/ephyr/ephyr_glamor_glx.c
@@ -0,0 +1,292 @@
+/*
+ * Copyright © 2013 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+/** @file ephyr_glamor_glx.c
+ *
+ * Separate file for hiding Xlib and GLX-using parts of xephyr from
+ * the rest of the server-struct-aware build.
+ */
+
+#include <stdlib.h>
+#include <X11/Xlib.h>
+#include <X11/Xlib-xcb.h>
+#include <xcb/xcb_aux.h>
+#include <pixman.h>
+#include <epoxy/glx.h>
+#include "ephyr_glamor_glx.h"
+#include "os.h"
+
+/** @{
+ *
+ * global state for Xephyr with glamor.
+ *
+ * Xephyr can render with multiple windows, but all the windows have
+ * to be on the same X connection and all have to have the same
+ * visual.
+ */
+static Display *dpy;
+static XVisualInfo *visual_info;
+static GLXFBConfig fb_config;
+/** @} */
+
+/**
+ * Per-screen state for Xephyr with glamor.
+ */
+struct ephyr_glamor {
+    GLXContext ctx;
+    Window win;
+    GLXWindow glx_win;
+
+    GLuint tex;
+
+    GLuint texture_shader;
+    GLuint texture_shader_position_loc;
+    GLuint texture_shader_texcoord_loc;
+};
+
+static GLint
+ephyr_glamor_compile_glsl_prog(GLenum type, const char *source)
+{
+    GLint ok;
+    GLint prog;
+
+    prog = glCreateShader(type);
+    glShaderSource(prog, 1, (const GLchar **) &source, NULL);
+    glCompileShader(prog);
+    glGetShaderiv(prog, GL_COMPILE_STATUS, &ok);
+    if (!ok) {
+        GLchar *info;
+        GLint size;
+
+        glGetShaderiv(prog, GL_INFO_LOG_LENGTH, &size);
+        info = malloc(size);
+        if (info) {
+            glGetShaderInfoLog(prog, size, NULL, info);
+            ErrorF("Failed to compile %s: %s\n",
+                   type == GL_FRAGMENT_SHADER ? "FS" : "VS", info);
+            ErrorF("Program source:\n%s", source);
+            free(info);
+        }
+        else
+            ErrorF("Failed to get shader compilation info.\n");
+        FatalError("GLSL compile failure\n");
+    }
+
+    return prog;
+}
+
+static GLuint
+ephyr_glamor_build_glsl_prog(GLuint vs, GLuint fs)
+{
+    GLint ok;
+    GLuint prog;
+
+    prog = glCreateProgram();
+    glAttachShader(prog, vs);
+    glAttachShader(prog, fs);
+
+    glLinkProgram(prog);
+    glGetProgramiv(prog, GL_LINK_STATUS, &ok);
+    if (!ok) {
+        GLchar *info;
+        GLint size;
+
+        glGetProgramiv(prog, GL_INFO_LOG_LENGTH, &size);
+        info = malloc(size);
+
+        glGetProgramInfoLog(prog, size, NULL, info);
+        ErrorF("Failed to link: %s\n", info);
+        FatalError("GLSL link failure\n");
+    }
+
+    return prog;
+}
+
+static void
+ephyr_glamor_setup_texturing_shader(struct ephyr_glamor *glamor)
+{
+    const char *vs_source =
+        "attribute vec2 texcoord;\n"
+        "attribute vec2 position;\n"
+        "varying vec2 t;\n"
+        "\n"
+        "void main()\n"
+        "{\n"
+        "    t = texcoord;\n"
+        "    gl_Position = vec4(position, 0, 1);\n"
+        "}\n";
+
+    const char *fs_source =
+        "varying vec2 t;\n"
+        "uniform sampler2D s; /* initially 0 */\n"
+        "\n"
+        "void main()\n"
+        "{\n"
+        "    gl_FragColor = texture2D(s, t);\n"
+        "}\n";
+
+    GLuint fs, vs, prog;
+
+    vs = ephyr_glamor_compile_glsl_prog(GL_VERTEX_SHADER, vs_source);
+    fs = ephyr_glamor_compile_glsl_prog(GL_FRAGMENT_SHADER, fs_source);
+    prog = ephyr_glamor_build_glsl_prog(vs, fs);
+
+    glamor->texture_shader = prog;
+    glamor->texture_shader_position_loc = glGetAttribLocation(prog, "position");
+    assert(glamor->texture_shader_position_loc != -1);
+    glamor->texture_shader_texcoord_loc = glGetAttribLocation(prog, "texcoord");
+    assert(glamor->texture_shader_texcoord_loc != -1);
+}
+
+xcb_connection_t *
+ephyr_glamor_connect(void)
+{
+    dpy = XOpenDisplay(NULL);
+    if (!dpy)
+        return NULL;
+
+    XSetEventQueueOwner(dpy, XCBOwnsEventQueue);
+
+    return XGetXCBConnection(dpy);
+}
+
+void
+ephyr_glamor_set_texture(struct ephyr_glamor *glamor, uint32_t tex)
+{
+    glamor->tex = tex;
+}
+
+void
+ephyr_glamor_damage_redisplay(struct ephyr_glamor *glamor,
+                              struct pixman_region16 *damage)
+{
+    /* Redraw the whole screen, since glXSwapBuffers leaves the back
+     * buffer undefined.
+     */
+    static const float position[] = {
+        -1, -1,
+         1, -1,
+         1,  1,
+        -1,  1,
+    };
+    static const float texcoords[] = {
+        0, 1,
+        1, 1,
+        1, 0,
+        0, 0,
+    };
+
+    glXMakeCurrent(dpy, glamor->glx_win, glamor->ctx);
+
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    glUseProgram(glamor->texture_shader);
+
+    glVertexAttribPointer(glamor->texture_shader_position_loc,
+                          2, GL_FLOAT, FALSE, 0, position);
+    glVertexAttribPointer(glamor->texture_shader_texcoord_loc,
+                          2, GL_FLOAT, FALSE, 0, texcoords);
+    glEnableVertexAttribArray(glamor->texture_shader_position_loc);
+    glEnableVertexAttribArray(glamor->texture_shader_texcoord_loc);
+
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, glamor->tex);
+    glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+
+    glDisableVertexAttribArray(glamor->texture_shader_position_loc);
+    glDisableVertexAttribArray(glamor->texture_shader_texcoord_loc);
+
+    glXSwapBuffers(dpy, glamor->glx_win);
+}
+
+struct ephyr_glamor *
+ephyr_glamor_glx_screen_init(xcb_window_t win)
+{
+    GLXContext ctx;
+    struct ephyr_glamor *glamor;
+    GLXWindow glx_win;
+
+    glamor = calloc(1, sizeof(struct ephyr_glamor));
+    if (!glamor) {
+        FatalError("malloc");
+        return NULL;
+    }
+
+    glx_win = glXCreateWindow(dpy, fb_config, win, NULL);
+
+    ctx = glXCreateContext(dpy, visual_info, NULL, True);
+    if (ctx == NULL)
+        FatalError("glXCreateContext failed\n");
+
+    if (!glXMakeCurrent(dpy, glx_win, ctx))
+        FatalError("glXMakeCurrent failed\n");
+
+    glamor->ctx = ctx;
+    glamor->win = win;
+    glamor->glx_win = glx_win;
+    ephyr_glamor_setup_texturing_shader(glamor);
+
+    return glamor;
+}
+
+void
+ephyr_glamor_glx_screen_fini(struct ephyr_glamor *glamor)
+{
+    glXMakeCurrent(dpy, None, NULL);
+    glXDestroyContext(dpy, glamor->ctx);
+    glXDestroyWindow(dpy, glamor->glx_win);
+
+    free(glamor);
+}
+
+xcb_visualtype_t *
+ephyr_glamor_get_visual(void)
+{
+    xcb_screen_t *xscreen =
+        xcb_aux_get_screen(XGetXCBConnection(dpy), DefaultScreen(dpy));
+    int attribs[] = {
+        GLX_RENDER_TYPE, GLX_RGBA_BIT,
+        GLX_DRAWABLE_TYPE, GLX_WINDOW_BIT,
+        GLX_RED_SIZE, 1,
+        GLX_GREEN_SIZE, 1,
+        GLX_BLUE_SIZE, 1,
+        GLX_DOUBLEBUFFER, 1,
+        None
+    };
+    int event_base = 0, error_base = 0, nelements;
+    GLXFBConfig *fbconfigs;
+
+    if (!glXQueryExtension (dpy, &error_base, &event_base))
+        FatalError("Couldn't find GLX extension\n");
+
+    fbconfigs = glXChooseFBConfig(dpy, DefaultScreen(dpy), attribs, &nelements);
+    if (!nelements)
+        FatalError("Couldn't choose an FBConfig\n");
+    fb_config = fbconfigs[0];
+    free(fbconfigs);
+
+    visual_info = glXGetVisualFromFBConfig(dpy, fb_config);
+    if (visual_info == NULL)
+        FatalError("Couldn't get RGB visual\n");
+
+    return xcb_aux_find_visual_by_id(xscreen, visual_info->visualid);
+}