mirror of
https://gitlab.gnome.org/GNOME/gtk.git
synced 2024-09-20 05:50:11 +00:00
038aac6275
This adds the new type GdkGLContext that wraps an OpenGL context for a particular native window. It also adds support for the gdk paint machinery to use OpenGL to draw everything. As soon as anyone creates a GL context for a native window we create a "paint context" for that GdkWindow and switch to using GL for painting it. This commit contains only an implementation for X11 (using GLX). The way painting works is that all client gl contexts draw into offscreen buffers rather than directly to the back buffer, and the way something gets onto the window is by using gdk_cairo_draw_from_gl() to draw part of that buffer onto the draw cairo context. As a fallback (if we're doing redirected drawing or some effect like a cairo_push_group()) we read back the gl buffer into memory and composite using cairo. This means that GL rendering works in all cases, including rendering to a PDF. However, this is not particularly fast. In the *typical* case, where we're drawing directly to the window in the regular paint loop we hit the fast path. The fast path uses opengl to draw the buffer to the window back buffer, either by blitting or texturing. Then we track the region that was drawn, and when the draw ends we paint the normal cairo surface to the window (using texture-from-pixmap in the X11 case, or texture from cairo image otherwise) in the regions where there is no gl painted. There are some complexities wrt layering of gl and cairo areas though: * We track via gdk_window_mark_paint_from_clip() whenever gtk is painting over a region we previously rendered with opengl (flushed_region). This area (needs_blend_region) is blended rather than copied at the end of the frame. * If we're drawing a gl texture with alpha we first copy the current cairo_surface inside the target region to the back buffer before we blend over it. These two operations allow us full stacking of transparent gl and cairo regions.
460 lines
17 KiB
C
460 lines
17 KiB
C
/* GDK - The GIMP Drawing Kit
|
|
* Copyright (C) 2005 Red Hat, Inc.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include "gdkcairo.h"
|
|
#include "gdkglcontextprivate.h"
|
|
|
|
#include "gdkinternals.h"
|
|
|
|
#include <epoxy/gl.h>
|
|
#include <math.h>
|
|
|
|
static cairo_user_data_key_t direct_key;
|
|
|
|
void
|
|
gdk_cairo_surface_mark_as_direct (cairo_surface_t *surface,
|
|
GdkWindow *window)
|
|
{
|
|
cairo_surface_set_user_data (surface, &direct_key,
|
|
g_object_ref (window), g_object_unref);
|
|
}
|
|
|
|
/* x,y,width,height describes a rectangle in the gl render buffer
|
|
coordinate space, and its top left corner is drawn at the current
|
|
position according to the cairo translation. */
|
|
/**
|
|
* gdk_cairo_draw_from_gl
|
|
* @cr: a cairo context
|
|
* @window: The window we're rendering for (not necessarily into)
|
|
* @source: The GL id of the source buffer
|
|
* @source_type: The type of the @source
|
|
* @buffer_scale: The scale-factor that the @source buffer is allocated for
|
|
* @x: The source x position in @source to start copying from in GL coordinates
|
|
* @y: The source y position in @source to start copying from in GL coordinates
|
|
* @width: The width of the region to draw
|
|
* @height: The height of the region to draw
|
|
*
|
|
* This is the main way to draw GL content in Gtk+. It takes a render buffer id
|
|
* (@source_type == #GL_RENDERBUFFER) or a texture id (@source_type == #GL_TEXTURE)
|
|
* and draws it onto @cr with an OVER operation, respecting the current clip.
|
|
*
|
|
* This will work for *all* cairo_t, as long as @window is realized, but the
|
|
* fallback implementation that reads back the pixels from the buffer may be
|
|
* used in the general case. In the case of direct drawing to a window with
|
|
* no special effects applied to @cr it will however use a more efficient
|
|
* approach.
|
|
*
|
|
* For #GL_RENDERBUFFER the code will always fall back to software for buffers
|
|
* with alpha components, so make sure you use #GL_TEXTURE if using alpha.
|
|
*/
|
|
void
|
|
gdk_cairo_draw_from_gl (cairo_t *cr,
|
|
GdkWindow *window,
|
|
int source,
|
|
int source_type,
|
|
int buffer_scale,
|
|
int x,
|
|
int y,
|
|
int width,
|
|
int height)
|
|
{
|
|
GdkGLContext *context;
|
|
cairo_surface_t *image;
|
|
cairo_matrix_t matrix;
|
|
int dx, dy, window_scale;
|
|
gboolean trivial_transform;
|
|
cairo_surface_t *group_target;
|
|
GdkWindow *direct_window, *impl_window;
|
|
GLuint framebuffer;
|
|
GLint alpha_size = 0;
|
|
cairo_region_t *clip_region;
|
|
|
|
impl_window = window->impl_window;
|
|
|
|
window_scale = gdk_window_get_scale_factor (impl_window);
|
|
|
|
context = gdk_window_get_paint_gl_context (window, NULL);
|
|
if (context == NULL)
|
|
{
|
|
g_warning ("gdk_cairo_draw_gl_render_buffer failed - no paint context");
|
|
return;
|
|
}
|
|
|
|
clip_region = gdk_cairo_region_from_clip (cr);
|
|
|
|
if (!gdk_gl_context_make_current (context))
|
|
g_error ("make current failed");
|
|
|
|
glGenFramebuffersEXT (1, &framebuffer);
|
|
glBindFramebufferEXT (GL_FRAMEBUFFER_EXT, framebuffer);
|
|
|
|
if (source_type == GL_RENDERBUFFER)
|
|
{
|
|
glGetRenderbufferParameteriv (GL_RENDERBUFFER, GL_RENDERBUFFER_ALPHA_SIZE, &alpha_size);
|
|
|
|
glBindRenderbufferEXT (GL_RENDERBUFFER_EXT, source);
|
|
glFramebufferRenderbufferEXT (GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
|
|
GL_RENDERBUFFER_EXT, source);
|
|
glBindFramebufferEXT(GL_DRAW_FRAMEBUFFER_EXT, 0);
|
|
}
|
|
else if (source_type == GL_TEXTURE)
|
|
{
|
|
glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_ALPHA_SIZE, &alpha_size);
|
|
|
|
glBindTexture (GL_TEXTURE_2D, source);
|
|
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
|
|
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
|
|
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
|
|
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
|
|
glFramebufferTexture2DEXT (GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
|
|
GL_TEXTURE_2D, source, 0);
|
|
glBindFramebufferEXT(GL_DRAW_FRAMEBUFFER_EXT, 0);
|
|
}
|
|
else
|
|
{
|
|
g_warning ("Unsupported gl source type %d\n", source_type);
|
|
return;
|
|
}
|
|
|
|
group_target = cairo_get_group_target (cr);
|
|
direct_window = cairo_surface_get_user_data (group_target, &direct_key);
|
|
|
|
cairo_get_matrix (cr, &matrix);
|
|
|
|
dx = matrix.x0;
|
|
dy = matrix.y0;
|
|
|
|
/* Trivial == integer-only translation */
|
|
trivial_transform =
|
|
(double)dx == matrix.x0 && (double)dy == matrix.y0 &&
|
|
matrix.xx == 1.0 && matrix.xy == 0.0 &&
|
|
matrix.yx == 0.0 && matrix.yy == 1.0;
|
|
|
|
/* For direct paint of non-alpha renderbuffer, we can
|
|
just do a bitblit */
|
|
if (source_type == GL_RENDERBUFFER &&
|
|
alpha_size == 0 &&
|
|
direct_window != NULL &&
|
|
direct_window->current_paint.use_gl &&
|
|
trivial_transform &&
|
|
clip_region != NULL)
|
|
{
|
|
int window_height;
|
|
int i;
|
|
|
|
/* Translate to impl coords */
|
|
cairo_region_translate (clip_region, dx, dy);
|
|
|
|
glEnable (GL_SCISSOR_TEST);
|
|
|
|
window_height = gdk_window_get_height (impl_window);
|
|
glDrawBuffer (GL_BACK);
|
|
|
|
#define FLIP_Y(_y) (window_height*window_scale - (_y))
|
|
|
|
for (i = 0; i < cairo_region_num_rectangles (clip_region); i++)
|
|
{
|
|
cairo_rectangle_int_t clip_rect, dest;
|
|
|
|
cairo_region_get_rectangle (clip_region, i, &clip_rect);
|
|
clip_rect.x *= window_scale;
|
|
clip_rect.y *= window_scale;
|
|
clip_rect.width *= window_scale;
|
|
clip_rect.height *= window_scale;
|
|
|
|
glScissor (clip_rect.x, FLIP_Y (clip_rect.y + clip_rect.height),
|
|
clip_rect.width, clip_rect.height);
|
|
|
|
dest.x = dx * window_scale;
|
|
dest.y = dy * window_scale;
|
|
dest.width = width * window_scale / buffer_scale;
|
|
dest.height = height * window_scale / buffer_scale;
|
|
|
|
if (gdk_rectangle_intersect (&clip_rect, &dest, &dest))
|
|
{
|
|
int clipped_src_x = x + (dest.x - dx * window_scale);
|
|
int clipped_src_y = y + (height - dest.height - (dest.y - dy * window_scale));
|
|
glBlitFramebufferEXT(clipped_src_x, clipped_src_y,
|
|
(clipped_src_x + dest.width), (clipped_src_y + dest.height),
|
|
dest.x, FLIP_Y(dest.y + dest.height),
|
|
dest.x + dest.width, FLIP_Y(dest.y),
|
|
GL_COLOR_BUFFER_BIT, GL_NEAREST);
|
|
if (impl_window->current_paint.flushed_region)
|
|
{
|
|
cairo_rectangle_int_t flushed_rect;
|
|
|
|
flushed_rect.x = dest.x / window_scale;
|
|
flushed_rect.y = dest.y / window_scale;
|
|
flushed_rect.width = (dest.x + dest.width + window_scale - 1) / window_scale - flushed_rect.x;
|
|
flushed_rect.height = (dest.y + dest.height + window_scale - 1) / window_scale - flushed_rect.y;
|
|
|
|
cairo_region_union_rectangle (impl_window->current_paint.flushed_region,
|
|
&flushed_rect);
|
|
cairo_region_subtract_rectangle (impl_window->current_paint.need_blend_region,
|
|
&flushed_rect);
|
|
}
|
|
}
|
|
}
|
|
|
|
glDisable (GL_SCISSOR_TEST);
|
|
|
|
#undef FLIP_Y
|
|
|
|
}
|
|
/* For direct paint of alpha or non-alpha textures we can use texturing */
|
|
else if (source_type == GL_TEXTURE &&
|
|
direct_window != NULL &&
|
|
direct_window->current_paint.use_gl &&
|
|
trivial_transform &&
|
|
clip_region != NULL)
|
|
{
|
|
int window_height;
|
|
GLint texture_width;
|
|
GLint texture_height;
|
|
int i;
|
|
|
|
/* Translate to impl coords */
|
|
cairo_region_translate (clip_region, dx, dy);
|
|
|
|
glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &texture_width);
|
|
glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &texture_height);
|
|
|
|
if (alpha_size != 0)
|
|
{
|
|
cairo_region_t *opaque_region, *blend_region;
|
|
|
|
opaque_region = cairo_region_copy (clip_region);
|
|
cairo_region_subtract (opaque_region, impl_window->current_paint.flushed_region);
|
|
cairo_region_subtract (opaque_region, impl_window->current_paint.need_blend_region);
|
|
|
|
if (!cairo_region_is_empty (opaque_region))
|
|
gdk_gl_texture_from_surface (impl_window->current_paint.surface,
|
|
opaque_region);
|
|
|
|
blend_region = cairo_region_copy (clip_region);
|
|
cairo_region_intersect (blend_region, impl_window->current_paint.need_blend_region);
|
|
|
|
glEnable (GL_BLEND);
|
|
if (!cairo_region_is_empty (blend_region))
|
|
gdk_gl_texture_from_surface (impl_window->current_paint.surface,
|
|
blend_region);
|
|
|
|
cairo_region_destroy (opaque_region);
|
|
cairo_region_destroy (blend_region);
|
|
}
|
|
glEnable (GL_SCISSOR_TEST);
|
|
glEnable (GL_TEXTURE_2D);
|
|
|
|
window_height = gdk_window_get_height (impl_window);
|
|
|
|
#define FLIP_Y(_y) (window_height*window_scale - (_y))
|
|
|
|
for (i = 0; i < cairo_region_num_rectangles (clip_region); i++)
|
|
{
|
|
cairo_rectangle_int_t clip_rect, dest;
|
|
|
|
cairo_region_get_rectangle (clip_region, i, &clip_rect);
|
|
|
|
clip_rect.x *= window_scale;
|
|
clip_rect.y *= window_scale;
|
|
clip_rect.width *= window_scale;
|
|
clip_rect.height *= window_scale;
|
|
|
|
glScissor (clip_rect.x, FLIP_Y (clip_rect.y + clip_rect.height),
|
|
clip_rect.width, clip_rect.height);
|
|
|
|
dest.x = dx * window_scale;
|
|
dest.y = dy * window_scale;
|
|
dest.width = width * window_scale / buffer_scale;
|
|
dest.height = height * window_scale / buffer_scale;
|
|
|
|
if (gdk_rectangle_intersect (&clip_rect, &dest, &dest))
|
|
{
|
|
int clipped_src_x = x + (dest.x - dx * window_scale);
|
|
int clipped_src_y = y + (height - dest.height - (dest.y - dy * window_scale));
|
|
|
|
glBegin (GL_QUADS);
|
|
glTexCoord2f (clipped_src_x / (float)texture_width, clipped_src_y / (float)texture_height);
|
|
glVertex2f (dest.x, FLIP_Y(dest.y + dest.height));
|
|
|
|
glTexCoord2f ((clipped_src_x + dest.width) / (float)texture_width, clipped_src_y / (float)texture_height);
|
|
glVertex2f (dest.x + dest.width, FLIP_Y(dest.y + dest.height));
|
|
|
|
glTexCoord2f ((clipped_src_x + dest.width) / (float)texture_width, (clipped_src_y + dest.height) / (float)texture_height);
|
|
glVertex2f (dest.x + dest.width, FLIP_Y(dest.y));
|
|
|
|
glTexCoord2f (clipped_src_x / (float)texture_width, (clipped_src_y + dest.height) / (float)texture_height);
|
|
glVertex2f (dest.x, FLIP_Y(dest.y));
|
|
glEnd();
|
|
|
|
if (impl_window->current_paint.flushed_region)
|
|
{
|
|
cairo_rectangle_int_t flushed_rect;
|
|
|
|
flushed_rect.x = dest.x / window_scale;
|
|
flushed_rect.y = dest.y / window_scale;
|
|
flushed_rect.width = (dest.x + dest.width + window_scale - 1) / window_scale - flushed_rect.x;
|
|
flushed_rect.height = (dest.y + dest.height + window_scale - 1) / window_scale - flushed_rect.y;
|
|
|
|
cairo_region_union_rectangle (impl_window->current_paint.flushed_region,
|
|
&flushed_rect);
|
|
cairo_region_subtract_rectangle (impl_window->current_paint.need_blend_region,
|
|
&flushed_rect);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (alpha_size != 0)
|
|
glDisable (GL_BLEND);
|
|
|
|
glDisable (GL_TEXTURE_2D);
|
|
glDisable (GL_SCISSOR_TEST);
|
|
|
|
#undef FLIP_Y
|
|
|
|
}
|
|
else
|
|
{
|
|
/* Software fallback */
|
|
|
|
/* TODO: avoid reading back non-required data due to dest clip */
|
|
image = cairo_surface_create_similar_image (cairo_get_target (cr),
|
|
(alpha_size == 0) ? CAIRO_FORMAT_RGB24 : CAIRO_FORMAT_ARGB32,
|
|
width, height);
|
|
|
|
#ifdef HAVE_CAIRO_SURFACE_SET_DEVICE_SCALE
|
|
cairo_surface_set_device_scale (image, buffer_scale, buffer_scale);
|
|
#endif
|
|
|
|
glPixelStorei (GL_PACK_ALIGNMENT, 4);
|
|
glPixelStorei (GL_PACK_ROW_LENGTH, cairo_image_surface_get_stride (image) / 4);
|
|
|
|
glReadPixels (x, y, width, height, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV,
|
|
cairo_image_surface_get_data (image));
|
|
|
|
glPixelStorei (GL_PACK_ROW_LENGTH, 0);
|
|
|
|
cairo_surface_mark_dirty (image);
|
|
|
|
/* Invert due to opengl having different origin */
|
|
cairo_scale (cr, 1, -1);
|
|
cairo_translate (cr, 0, -height / buffer_scale);
|
|
|
|
cairo_set_source_surface (cr, image, 0, 0);
|
|
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
|
|
cairo_paint (cr);
|
|
|
|
cairo_surface_destroy (image);
|
|
}
|
|
|
|
glDrawBuffer (GL_BACK);
|
|
glReadBuffer(GL_BACK);
|
|
|
|
glBindFramebufferEXT (GL_FRAMEBUFFER_EXT, 0);
|
|
glDeleteFramebuffersEXT (1, &framebuffer);
|
|
|
|
if (clip_region)
|
|
cairo_region_destroy (clip_region);
|
|
}
|
|
|
|
void
|
|
gdk_gl_texture_from_surface (cairo_surface_t *surface,
|
|
cairo_region_t *region)
|
|
{
|
|
GdkGLContext *current;
|
|
cairo_surface_t *image;
|
|
double device_x_offset, device_y_offset;
|
|
cairo_rectangle_int_t rect, e;
|
|
int n_rects, i;
|
|
GdkWindow *window;
|
|
int window_height;
|
|
unsigned int texture_id;
|
|
int window_scale;
|
|
double sx, sy;
|
|
|
|
current = gdk_gl_context_get_current ();
|
|
if (current &&
|
|
GDK_GL_CONTEXT_GET_CLASS (current)->texture_from_surface &&
|
|
GDK_GL_CONTEXT_GET_CLASS (current)->texture_from_surface (current, surface, region))
|
|
return;
|
|
|
|
/* Software fallback */
|
|
|
|
window = gdk_gl_context_get_window (gdk_gl_context_get_current ());
|
|
window_scale = gdk_window_get_scale_factor (window);
|
|
window_height = gdk_window_get_height (window);
|
|
|
|
sx = sy = 1;
|
|
#ifdef HAVE_CAIRO_SURFACE_SET_DEVICE_SCALE
|
|
cairo_surface_get_device_scale (window->current_paint.surface, &sx, &sy);
|
|
#endif
|
|
|
|
cairo_surface_get_device_offset (surface,
|
|
&device_x_offset, &device_y_offset);
|
|
|
|
glGenTextures (1, &texture_id);
|
|
glBindTexture (GL_TEXTURE_RECTANGLE_ARB, texture_id);
|
|
glEnable (GL_TEXTURE_RECTANGLE_ARB);
|
|
|
|
n_rects = cairo_region_num_rectangles (region);
|
|
for (i = 0; i < n_rects; i++)
|
|
{
|
|
cairo_region_get_rectangle (region, i, &rect);
|
|
|
|
glScissor (rect.x * window_scale, (window_height - rect.y - rect.height) * window_scale,
|
|
rect.width * window_scale, rect.height * window_scale);
|
|
|
|
e = rect;
|
|
e.x *= sx;
|
|
e.y *= sy;
|
|
e.x += (int)device_x_offset;
|
|
e.y += (int)device_y_offset;
|
|
e.width *= sx;
|
|
e.height *= sy;
|
|
image = cairo_surface_map_to_image (surface, &e);
|
|
|
|
glPixelStorei (GL_UNPACK_ALIGNMENT, 4);
|
|
glPixelStorei (GL_UNPACK_ROW_LENGTH, cairo_image_surface_get_stride (image)/4);
|
|
glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 4, e.width, e.height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV,
|
|
cairo_image_surface_get_data (image));
|
|
glPixelStorei (GL_UNPACK_ROW_LENGTH, 0);
|
|
|
|
cairo_surface_unmap_image (surface, image);
|
|
|
|
#define FLIP_Y(_y) (window_height - (_y))
|
|
|
|
glBegin (GL_QUADS);
|
|
glTexCoord2f (0.0f * sx, rect.height * sy);
|
|
glVertex2f (rect.x * window_scale, FLIP_Y(rect.y + rect.height) * window_scale);
|
|
|
|
glTexCoord2f (rect.width * sx, rect.height * sy);
|
|
glVertex2f ((rect.x + rect.width) * window_scale, FLIP_Y(rect.y + rect.height) * window_scale);
|
|
|
|
glTexCoord2f (rect.width * sx, 0.0f * sy);
|
|
glVertex2f ((rect.x + rect.width) * window_scale, FLIP_Y(rect.y) * window_scale);
|
|
|
|
glTexCoord2f (0.0f * sx, 0.0f * sy);
|
|
glVertex2f (rect.x * window_scale, FLIP_Y(rect.y) * window_scale);
|
|
glEnd();
|
|
}
|
|
|
|
glDisable (GL_TEXTURE_RECTANGLE_ARB);
|
|
glDeleteTextures (1, &texture_id);
|
|
}
|