gtk/gdk/gdkgl.c
Matthias Clasen 4c150d8eb5 The big versioning cleanup
Remove all the old 2.x and 3.x version annotations.
GTK+ 4 is a new start, and from the perspective of a
GTK+ 4 developer all these APIs have been around since
the beginning.
2018-02-06 01:16:32 -05:00

614 lines
20 KiB
C

/* GDK - The GIMP Drawing Kit
* Copyright (C) 2014 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>
#include <string.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);
}
static const char *
get_vertex_type_name (int type)
{
switch (type)
{
case GL_VERTEX_SHADER:
return "vertex";
case GL_GEOMETRY_SHADER:
return "geometry";
case GL_FRAGMENT_SHADER:
return "fragment";
default:
return "unknown";
}
}
static guint
create_shader (int type,
const char *code)
{
guint shader;
int status;
shader = glCreateShader (type);
glShaderSource (shader, 1, &code, NULL);
glCompileShader (shader);
glGetShaderiv (shader, GL_COMPILE_STATUS, &status);
if (status == GL_FALSE)
{
int log_len;
char *buffer;
glGetShaderiv (shader, GL_INFO_LOG_LENGTH, &log_len);
buffer = g_malloc (log_len + 1);
glGetShaderInfoLog (shader, log_len, NULL, buffer);
g_warning ("Compile failure in %s shader:\n%s", get_vertex_type_name (type), buffer);
g_free (buffer);
glDeleteShader (shader);
return 0;
}
return shader;
}
static void
make_program (GdkGLContextProgram *program,
const char *vertex_shader_path,
const char *fragment_shader_path)
{
guint vertex_shader, fragment_shader;
GBytes *source;
int status;
source = g_resources_lookup_data (vertex_shader_path, 0, NULL);
g_assert (source != NULL);
vertex_shader = create_shader (GL_VERTEX_SHADER, g_bytes_get_data (source, NULL));
g_bytes_unref (source);
if (vertex_shader == 0)
return;
source = g_resources_lookup_data (fragment_shader_path, 0, NULL);
g_assert (source != NULL);
fragment_shader = create_shader (GL_FRAGMENT_SHADER, g_bytes_get_data (source, NULL));
g_bytes_unref (source);
if (fragment_shader == 0)
{
glDeleteShader (vertex_shader);
return;
}
program->program = glCreateProgram ();
glAttachShader (program->program, vertex_shader);
glAttachShader (program->program, fragment_shader);
glLinkProgram (program->program);
glDeleteShader (vertex_shader);
glDeleteShader (fragment_shader);
glGetProgramiv (program->program, GL_LINK_STATUS, &status);
if (status == GL_FALSE)
{
int log_len;
char *buffer;
glGetProgramiv (program->program, GL_INFO_LOG_LENGTH, &log_len);
buffer = g_malloc (log_len + 1);
glGetProgramInfoLog (program->program, log_len, NULL, buffer);
g_warning ("Linker failure: %s\n", buffer);
g_free (buffer);
glDeleteProgram (program->program);
}
program->position_location = glGetAttribLocation (program->program, "position");
program->uv_location = glGetAttribLocation (program->program, "uv");
program->map_location = glGetUniformLocation (program->program, "map");
program->flip_location = glGetUniformLocation (program->program, "flipColors");
}
static void
bind_vao (GdkGLContextPaintData *paint_data)
{
if (paint_data->vertex_array_object == 0)
{
glGenVertexArrays (1, &paint_data->vertex_array_object);
/* ATM we only use one VAO, so always bind it */
glBindVertexArray (paint_data->vertex_array_object);
}
}
static void
use_texture_gles_program (GdkGLContextPaintData *paint_data)
{
if (paint_data->texture_2d_quad_program.program == 0)
make_program (&paint_data->texture_2d_quad_program,
"/org/gtk/libgdk/glsl/gles2-texture.vs.glsl",
"/org/gtk/libgdk/glsl/gles2-texture.fs.glsl");
if (paint_data->current_program != &paint_data->texture_2d_quad_program)
{
paint_data->current_program = &paint_data->texture_2d_quad_program;
glUseProgram (paint_data->current_program->program);
}
}
static void
use_texture_2d_program (GdkGLContextPaintData *paint_data)
{
const char *vertex_shader_path = paint_data->is_legacy
? "/org/gtk/libgdk/glsl/gl2-texture-2d.vs.glsl"
: "/org/gtk/libgdk/glsl/gl3-texture-2d.vs.glsl";
const char *fragment_shader_path = paint_data->is_legacy
? "/org/gtk/libgdk/glsl/gl2-texture-2d.fs.glsl"
: "/org/gtk/libgdk/glsl/gl3-texture-2d.fs.glsl";
if (paint_data->texture_2d_quad_program.program == 0)
make_program (&paint_data->texture_2d_quad_program, vertex_shader_path, fragment_shader_path);
if (paint_data->current_program != &paint_data->texture_2d_quad_program)
{
paint_data->current_program = &paint_data->texture_2d_quad_program;
glUseProgram (paint_data->current_program->program);
}
}
static void
use_texture_rect_program (GdkGLContextPaintData *paint_data)
{
const char *vertex_shader_path = paint_data->is_legacy
? "/org/gtk/libgdk/glsl/gl2-texture-rect.vs.glsl"
: "/org/gtk/libgdk/glsl/gl3-texture-rect.vs.glsl";
const char *fragment_shader_path = paint_data->is_legacy
? "/org/gtk/libgdk/glsl/gl2-texture-rect.fs.glsl"
: "/org/gtk/libgdk/glsl/gl3-texture-rect.vs.glsl";
if (paint_data->texture_rect_quad_program.program == 0)
make_program (&paint_data->texture_rect_quad_program, vertex_shader_path, fragment_shader_path);
if (paint_data->current_program != &paint_data->texture_rect_quad_program)
{
paint_data->current_program = &paint_data->texture_rect_quad_program;
glUseProgram (paint_data->current_program->program);
}
}
void
gdk_gl_texture_quads (GdkGLContext *paint_context,
guint texture_target,
int n_quads,
GdkTexturedQuad *quads,
gboolean flip_colors)
{
GdkGLContextPaintData *paint_data = gdk_gl_context_get_paint_data (paint_context);
GdkGLContextProgram *program;
GdkWindow *window = gdk_gl_context_get_window (paint_context);
int window_scale = gdk_window_get_scale_factor (window);
float w = gdk_window_get_width (window) * window_scale;
float h = gdk_window_get_height (window) * window_scale;
int i;
float *vertex_buffer_data;
bind_vao (paint_data);
if (paint_data->tmp_vertex_buffer == 0)
glGenBuffers(1, &paint_data->tmp_vertex_buffer);
if (paint_data->use_es)
use_texture_gles_program (paint_data);
else
{
if (texture_target == GL_TEXTURE_RECTANGLE_ARB)
use_texture_rect_program (paint_data);
else
use_texture_2d_program (paint_data);
}
program = paint_data->current_program;
/* Use texture unit 0 */
glActiveTexture (GL_TEXTURE0);
glUniform1i(program->map_location, 0);
/* Flip 'R' and 'B' colors on GLES, if necessary */
if (gdk_gl_context_get_use_es (paint_context))
glUniform1i (program->flip_location, flip_colors ? 1 : 0);
glEnableVertexAttribArray (program->position_location);
glEnableVertexAttribArray (program->uv_location);
glBindBuffer (GL_ARRAY_BUFFER, paint_data->tmp_vertex_buffer);
glVertexAttribPointer (program->position_location, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 4, NULL);
glVertexAttribPointer (program->uv_location, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 4, (void *) (sizeof(float) * 2));
#define VERTEX_SIZE 4
#define QUAD_N_VERTICES 6
#define QUAD_SIZE (VERTEX_SIZE * QUAD_N_VERTICES)
vertex_buffer_data = g_new (float, n_quads * QUAD_SIZE);
for (i = 0; i < n_quads; i++)
{
GdkTexturedQuad *quad = &quads[i];
float vertex_data[] = {
(quad->x1 * 2) / w - 1, (quad->y1 * 2) / h - 1, quad->u1, quad->v1,
(quad->x1 * 2) / w - 1, (quad->y2 * 2) / h - 1, quad->u1, quad->v2,
(quad->x2 * 2) / w - 1, (quad->y1 * 2) / h - 1, quad->u2, quad->v1,
(quad->x2 * 2) / w - 1, (quad->y2 * 2) / h - 1, quad->u2, quad->v2,
(quad->x1 * 2) / w - 1, (quad->y2 * 2) / h - 1, quad->u1, quad->v2,
(quad->x2 * 2) / w - 1, (quad->y1 * 2) / h - 1, quad->u2, quad->v1,
};
float *vertex = &vertex_buffer_data[i * QUAD_SIZE];
memcpy (vertex, vertex_data, sizeof(vertex_data));
}
glBufferData (GL_ARRAY_BUFFER, sizeof(float) * n_quads * QUAD_SIZE, vertex_buffer_data, GL_STREAM_DRAW);
glDrawArrays (GL_TRIANGLES, 0, n_quads * QUAD_N_VERTICES);
g_free (vertex_buffer_data);
glDisableVertexAttribArray (program->position_location);
glDisableVertexAttribArray (program->uv_location);
}
/* 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.
* The top left corner of the rectangle specified by @x, @y, @width and @height
* will be drawn at the current (0,0) position of the cairo_t.
*
* 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.
*
* Calling this may change the current GL context.
*/
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 *paint_context;
cairo_surface_t *image;
cairo_matrix_t matrix;
guint framebuffer;
int alpha_size = 0;
cairo_region_t *clip_region;
GdkGLContextPaintData *paint_data;
int major, minor, version;
paint_context = gdk_window_get_paint_gl_context (window, NULL);
if (paint_context == NULL)
{
g_warning ("gdk_cairo_draw_gl_render_buffer failed - no paint context");
return;
}
clip_region = gdk_cairo_region_from_clip (cr);
gdk_gl_context_make_current (paint_context);
paint_data = gdk_gl_context_get_paint_data (paint_context);
if (paint_data->tmp_framebuffer == 0)
glGenFramebuffersEXT (1, &paint_data->tmp_framebuffer);
if (source_type == GL_RENDERBUFFER)
{
glBindRenderbuffer (GL_RENDERBUFFER, source);
glGetRenderbufferParameteriv (GL_RENDERBUFFER, GL_RENDERBUFFER_ALPHA_SIZE, &alpha_size);
}
else if (source_type == GL_TEXTURE)
{
glBindTexture (GL_TEXTURE_2D, source);
if (gdk_gl_context_get_use_es (paint_context))
alpha_size = 1;
else
glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_ALPHA_SIZE, &alpha_size);
}
else
{
g_warning ("Unsupported gl source type %d\n", source_type);
return;
}
cairo_get_matrix (cr, &matrix);
gdk_gl_context_get_version (paint_context, &major, &minor);
version = major * 100 + minor;
/* TODO: Use glTexSubImage2D() and do a row-by-row copy to replace
* the GL_UNPACK_ROW_LENGTH support
*/
if (gdk_gl_context_get_use_es (paint_context) &&
!(version >= 300 || gdk_gl_context_has_unpack_subimage (paint_context)))
goto out;
/* 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);
cairo_surface_set_device_scale (image, buffer_scale, buffer_scale);
framebuffer = paint_data->tmp_framebuffer;
glBindFramebufferEXT (GL_FRAMEBUFFER_EXT, framebuffer);
if (source_type == GL_RENDERBUFFER)
{
/* Create a framebuffer with the source renderbuffer and
make it the current target for reads */
glFramebufferRenderbufferEXT (GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
GL_RENDERBUFFER_EXT, source);
}
else
{
glFramebufferTexture2DEXT (GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
GL_TEXTURE_2D, source, 0);
}
glPixelStorei (GL_PACK_ALIGNMENT, 4);
glPixelStorei (GL_PACK_ROW_LENGTH, cairo_image_surface_get_stride (image) / 4);
/* The implicit format conversion is going to make this path slower */
if (!gdk_gl_context_get_use_es (paint_context))
glReadPixels (x, y, width, height, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV,
cairo_image_surface_get_data (image));
else
glReadPixels (x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE,
cairo_image_surface_get_data (image));
glPixelStorei (GL_PACK_ROW_LENGTH, 0);
glBindFramebufferEXT (GL_FRAMEBUFFER_EXT, 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);
out:
if (clip_region)
cairo_region_destroy (clip_region);
}
/* This is always called with the paint context current */
void
gdk_gl_texture_from_surface (cairo_surface_t *surface,
cairo_region_t *region)
{
GdkGLContext *paint_context;
GdkDisplay *display;
cairo_surface_t *image;
double device_x_offset, device_y_offset;
cairo_rectangle_int_t rect, e;
int n_rects, i;
GdkWindow *window;
int unscaled_window_height;
unsigned int texture_id;
int window_scale;
double sx, sy;
float umax, vmax;
gboolean use_texture_rectangle;
guint target;
paint_context = gdk_gl_context_get_current ();
if (paint_context)
display = gdk_draw_context_get_display (GDK_DRAW_CONTEXT (paint_context));
else
display = NULL;
if (paint_context &&
GDK_DISPLAY_DEBUG_CHECK (display, GL_SOFTWARE) == 0 &&
GDK_GL_CONTEXT_GET_CLASS (paint_context)->texture_from_surface &&
GDK_GL_CONTEXT_GET_CLASS (paint_context)->texture_from_surface (paint_context, surface, region))
return;
/* Software fallback */
use_texture_rectangle = gdk_gl_context_use_texture_rectangle (paint_context);
window = gdk_gl_context_get_window (paint_context);
window_scale = gdk_window_get_scale_factor (window);
gdk_window_get_unscaled_size (window, NULL, &unscaled_window_height);
sx = sy = 1;
cairo_surface_get_device_scale (surface, &sx, &sy);
cairo_surface_get_device_offset (surface, &device_x_offset, &device_y_offset);
glGenTextures (1, &texture_id);
if (use_texture_rectangle)
target = GL_TEXTURE_RECTANGLE_ARB;
else
target = GL_TEXTURE_2D;
glBindTexture (target, texture_id);
glEnable (GL_SCISSOR_TEST);
glTexParameteri (target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri (target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri (target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri (target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
n_rects = cairo_region_num_rectangles (region);
#define FLIP_Y(_y) (unscaled_window_height - (_y))
for (i = 0; i < n_rects; i++)
{
cairo_region_get_rectangle (region, i, &rect);
glScissor (rect.x * window_scale, FLIP_Y ((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);
gdk_gl_context_upload_texture (paint_context,
cairo_image_surface_get_data (image),
e.width,
e.height,
cairo_image_surface_get_stride (image),
target);
cairo_surface_unmap_image (surface, image);
if (use_texture_rectangle)
{
umax = rect.width * sx;
vmax = rect.height * sy;
}
else
{
umax = 1.0;
vmax = 1.0;
}
{
GdkTexturedQuad quad = {
rect.x * window_scale, FLIP_Y(rect.y * window_scale),
(rect.x + rect.width) * window_scale, FLIP_Y((rect.y + rect.height) * window_scale),
0, 0,
umax, vmax,
};
/* We don't want to combine the quads here, because they have different textures.
* And we don't want to upload the unused source areas to make it one texture. */
gdk_gl_texture_quads (paint_context, target, 1, &quad, TRUE);
}
}
#undef FLIP_Y
glDisable (GL_SCISSOR_TEST);
glDeleteTextures (1, &texture_id);
}
/**
* gdk_cairo_surface_upload_to_gl:
* @surface: a Cairo surface
* @target: a GL texture target
* @width: the width of the texture @target
* @height: the height of the texture @target
* @context: (nullable): a #GdkGLContext, or %NULL to use the currently
* bound context
*
* Uploads the contents of a Cairo @surface to a GL texture @target.
*/
void
gdk_cairo_surface_upload_to_gl (cairo_surface_t *surface,
int target,
int width,
int height,
GdkGLContext *context)
{
cairo_rectangle_int_t rect;
cairo_surface_t *tmp;
double device_x_offset, device_y_offset;
g_return_if_fail (surface != NULL);
g_return_if_fail (context == NULL || GDK_IS_GL_CONTEXT (context));
if (context == NULL)
context = gdk_gl_context_get_current ();
cairo_surface_flush (surface);
cairo_surface_get_device_offset (surface, &device_x_offset, &device_y_offset);
rect.x = (int) device_x_offset;
rect.y = (int) device_y_offset;
rect.width = width;
rect.height = height;
tmp = cairo_surface_map_to_image (surface, &rect);
gdk_gl_context_upload_texture (context,
cairo_image_surface_get_data (tmp),
rect.width,
rect.height,
cairo_image_surface_get_stride (tmp),
target);
cairo_surface_unmap_image (surface, tmp);
}