[Qemu-devel] [PATCH v2 4/7] console-gl: add opengl rendering helper functions

[Gerd Hoffmann <kraxel@redhat.com>]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 configure            |   2 +-
 include/ui/console.h |  31 ++++++
 ui/Makefile.objs     |   5 +
 ui/console-gl.c      | 286 +++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 323 insertions(+), 1 deletion(-)
 create mode 100644 ui/console-gl.c

diff --git a/configure b/configure
index 6d673c1..e6b29a6 100755
--- a/configure
+++ b/configure
@@ -3069,7 +3069,7 @@ libs_softmmu="$libs_softmmu $fdt_libs"
 ##########################################
 # opengl probe (for sdl2, milkymist-tmu2)
 if test "$opengl" != "no" ; then
-  opengl_pkgs="gl"
+  opengl_pkgs="gl glesv2"
   if $pkg_config $opengl_pkgs x11; then
     opengl_cflags="$($pkg_config --libs $opengl_pkgs) $x11_cflags"
     opengl_libs="$($pkg_config --libs $opengl_pkgs) $x11_libs"
diff --git a/include/ui/console.h b/include/ui/console.h
index 22ef8ca..9157b64 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -9,6 +9,11 @@
 #include "qapi-types.h"
 #include "qapi/error.h"
 
+#ifdef CONFIG_OPENGL
+# include <GLES2/gl2.h>
+# include <GLES2/gl2ext.h>
+#endif
+
 /* keyboard/mouse support */
 
 #define MOUSE_EVENT_LBUTTON 0x01
@@ -118,6 +123,11 @@ struct DisplaySurface {
     pixman_format_code_t format;
     pixman_image_t *image;
     uint8_t flags;
+#ifdef CONFIG_OPENGL
+    GLenum glformat;
+    GLenum gltype;
+    GLuint texture;
+#endif
 };
 
 typedef struct QemuUIInfo {
@@ -320,6 +330,27 @@ void qemu_console_copy(QemuConsole *con, int src_x, int src_y,
 DisplaySurface *qemu_console_surface(QemuConsole *con);
 DisplayState *qemu_console_displaystate(QemuConsole *console);
 
+/* console-gl.c */
+typedef struct ConsoleGLState ConsoleGLState;
+#ifdef CONFIG_OPENGL
+ConsoleGLState *console_gl_init_context(void);
+void console_gl_fini_context(ConsoleGLState *gls);
+bool console_gl_check_format(DisplayChangeListener *dcl,
+                             pixman_format_code_t format);
+void surface_gl_create_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface);
+void surface_gl_update_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface,
+                               int x, int y, int w, int h);
+void surface_gl_render_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface);
+void surface_gl_destroy_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface);
+void surface_gl_setup_viewport(ConsoleGLState *gls,
+                               DisplaySurface *surface,
+                               int ww, int wh);
+#endif
+
 /* sdl.c */
 void sdl_display_init(DisplayState *ds, int full_screen, int no_frame);
 
diff --git a/ui/Makefile.objs b/ui/Makefile.objs
index 13b5cfb..3173778 100644
--- a/ui/Makefile.objs
+++ b/ui/Makefile.objs
@@ -24,4 +24,9 @@ sdl.mo-objs := sdl2.o sdl2-input.o sdl2-2d.o
 endif
 sdl.mo-cflags := $(SDL_CFLAGS)
 
+ifeq ($(CONFIG_OPENGL),y)
+common-obj-y += console-gl.o
+libs_softmmu += $(OPENGL_LIBS)
+endif
+
 gtk.o-cflags := $(GTK_CFLAGS) $(VTE_CFLAGS)
diff --git a/ui/console-gl.c b/ui/console-gl.c
new file mode 100644
index 0000000..589c682
--- /dev/null
+++ b/ui/console-gl.c
@@ -0,0 +1,286 @@
+/*
+ * QEMU graphical console -- opengl helper bits
+ *
+ * Copyright (c) 2014 Red Hat
+ *
+ * Authors:
+ *    Gerd Hoffmann <kraxel@redhat.com>
+ *
+ * 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 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.
+ */
+#include "qemu-common.h"
+#include "ui/console.h"
+
+struct ConsoleGLState {
+    GLint texture_blit_prog;
+};
+
+/* ---------------------------------------------------------------------- */
+
+static GLchar texture_blit_vert_src[] =
+    "\n"
+    "#version 300 es\n"
+    "\n"
+    "in vec2  in_position;\n"
+    "in vec2  in_tex_coord;\n"
+    "out vec2 ex_tex_coord;\n"
+    "\n"
+    "void main(void) {\n"
+    "    gl_Position = vec4(in_position.x, in_position.y, 0.0, 1.0);\n"
+    "    ex_tex_coord = in_tex_coord;\n"
+    "}\n"
+    "\n";
+
+static GLchar texture_blit_frag_src[] =
+    "\n"
+    "#version 300 es\n"
+    "\n"
+    "uniform sampler2D image;\n"
+    "in  highp vec2 ex_tex_coord;\n"
+    "out highp vec4 out_frag_color;\n"
+    "\n"
+    "void main(void) {\n"
+    "     out_frag_color = texture(image, ex_tex_coord);\n"
+    "}\n"
+    "\n";
+
+static void gl_run_texture_blit(ConsoleGLState *gls)
+{
+    GLfloat in_position[] = {
+        -1,  1,
+        -1, -1,
+        1,  -1,
+        -1,  1,
+        1,   1,
+        1,  -1,
+    };
+    GLfloat in_tex_coord[] = {
+        0, 0,
+        0, 1,
+        1, 1,
+        0, 0,
+        1, 0,
+        1, 1,
+    };
+    GLint l_position;
+    GLint l_tex_coord;
+
+    glUseProgram(gls->texture_blit_prog);
+    l_position = glGetAttribLocation(gls->texture_blit_prog, "in_position");
+    l_tex_coord = glGetAttribLocation(gls->texture_blit_prog, "in_tex_coord");
+    glVertexAttribPointer(l_position, 2, GL_FLOAT, GL_FALSE, 0, in_position);
+    glVertexAttribPointer(l_tex_coord, 2, GL_FLOAT, GL_FALSE, 0, in_tex_coord);
+    glEnableVertexAttribArray(l_position);
+    glEnableVertexAttribArray(l_tex_coord);
+    glDrawArrays(GL_TRIANGLE_STRIP, l_position, 6);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static GLuint gl_create_compile_shader(GLenum type, const GLchar *src)
+{
+    GLuint shader;
+    GLint status, length;
+    char *errmsg;
+
+    shader = glCreateShader(type);
+    glShaderSource(shader, 1, &src, 0);
+    glCompileShader(shader);
+
+    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
+    if (!status) {
+        glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &length);
+        errmsg = malloc(length);
+        glGetShaderInfoLog(shader, length, &length, errmsg);
+        fprintf(stderr, "%s: compile %s error\n%s\n", __func__,
+                (type == GL_VERTEX_SHADER) ? "vertex" : "fragment",
+                errmsg);
+        free(errmsg);
+        return 0;
+    }
+    return shader;
+}
+
+static GLuint gl_create_link_program(GLuint vert, GLuint frag)
+{
+    GLuint program;
+    GLint status, length;
+    char *errmsg;
+
+    program = glCreateProgram();
+    glAttachShader(program, vert);
+    glAttachShader(program, frag);
+    glLinkProgram(program);
+
+    glGetProgramiv(program, GL_LINK_STATUS, &status);
+    if (!status) {
+        glGetProgramiv(program, GL_INFO_LOG_LENGTH, &length);
+        errmsg = malloc(length);
+        glGetProgramInfoLog(program, length, &length, errmsg);
+        fprintf(stderr, "%s: link program: %s\n", __func__, errmsg);
+        free(errmsg);
+        return 0;
+    }
+    return program;
+}
+
+static GLuint gl_create_compile_link_program(const GLchar *vert_src,
+                                             const GLchar *frag_src)
+{
+    GLuint vert_shader, frag_shader;
+
+    vert_shader = gl_create_compile_shader(GL_VERTEX_SHADER, vert_src);
+    frag_shader = gl_create_compile_shader(GL_FRAGMENT_SHADER, frag_src);
+    if (!vert_shader || !frag_shader) {
+        return 0;
+    }
+
+    return gl_create_link_program(vert_shader, frag_shader);
+}
+
+/* ---------------------------------------------------------------------- */
+
+ConsoleGLState *console_gl_init_context(void)
+{
+    ConsoleGLState *gls = g_new0(ConsoleGLState, 1);
+
+    gls->texture_blit_prog = gl_create_compile_link_program
+        (texture_blit_vert_src, texture_blit_frag_src);
+    if (!gls->texture_blit_prog) {
+        exit(1);
+    }
+
+    return gls;
+}
+
+void console_gl_fini_context(ConsoleGLState *gls)
+{
+    if (!gls) {
+        return;
+    }
+    g_free(gls);
+}
+
+bool console_gl_check_format(DisplayChangeListener *dcl,
+                             pixman_format_code_t format)
+{
+    switch (format) {
+    case PIXMAN_BE_b8g8r8x8:
+    case PIXMAN_BE_b8g8r8a8:
+    case PIXMAN_r5g6b5:
+        return true;
+    default:
+        return false;
+    }
+}
+
+void surface_gl_create_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface)
+{
+    assert(gls);
+
+    switch (surface->format) {
+    case PIXMAN_BE_b8g8r8x8:
+    case PIXMAN_BE_b8g8r8a8:
+        surface->glformat = GL_BGRA_EXT;
+        surface->gltype = GL_UNSIGNED_BYTE;
+        break;
+    case PIXMAN_r5g6b5:
+        surface->glformat = GL_RGB;
+        surface->gltype = GL_UNSIGNED_SHORT_5_6_5;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    glGenTextures(1, &surface->texture);
+    glEnable(GL_TEXTURE_2D);
+    glBindTexture(GL_TEXTURE_2D, surface->texture);
+    glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT,
+                  surface_stride(surface) / surface_bytes_per_pixel(surface));
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
+                 surface_width(surface),
+                 surface_height(surface),
+                 0, surface->glformat, surface->gltype,
+                 surface_data(surface));
+
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+}
+
+void surface_gl_update_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface,
+                               int x, int y, int w, int h)
+{
+    uint8_t *data = (void *)surface_data(surface);
+
+    assert(gls);
+
+    glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT,
+                  surface_stride(surface) / surface_bytes_per_pixel(surface));
+    glTexSubImage2D(GL_TEXTURE_2D, 0,
+                    x, y, w, h,
+                    surface->glformat, surface->gltype,
+                    data + surface_stride(surface) * y
+                    + surface_bytes_per_pixel(surface) * x);
+}
+
+void surface_gl_render_texture(ConsoleGLState *gls,
+                               DisplaySurface *surface)
+{
+    assert(gls);
+
+    glClearColor(0.1f, 0.1f, 0.1f, 0.0f);
+    glClear(GL_COLOR_BUFFER_BIT);
+
+    gl_run_texture_blit(gls);
+}
+
+void surface_gl_destroy_texture(ConsoleGLState *gls,
+                                DisplaySurface *surface)
+{
+    if (!surface || !surface->texture) {
+        return;
+    }
+    glDeleteTextures(1, &surface->texture);
+    surface->texture = 0;
+}
+
+void surface_gl_setup_viewport(ConsoleGLState *gls,
+                               DisplaySurface *surface,
+                               int ww, int wh)
+{
+    int gw, gh, stripe;
+    float sw, sh;
+
+    assert(gls);
+
+    gw = surface_width(surface);
+    gh = surface_height(surface);
+
+    sw = (float)ww/gw;
+    sh = (float)wh/gh;
+    if (sw < sh) {
+        stripe = wh - wh*sw/sh;
+        glViewport(0, stripe / 2, ww, wh - stripe);
+    } else {
+        stripe = ww - ww*sh/sw;
+        glViewport(stripe / 2, 0, ww - stripe, wh);
+    }
+}
-- 
1.8.3.1