mutter/cogl/driver/gl/cogl-texture-2d-gl.c
Neil Roberts ff11a2b207 Use GL_ARB_texture_swizzle to emulate GL_ALPHA textures
The core profile of GL3 has removed support for component-alpha
textures. Previously the GL3 driver would just ignore this and try to
create them anyway. This would generate a GL error on Mesa.

To fix this the GL texture driver will now create a GL_RED texture
when GL_ALPHA textures are not supported natively. It will then set a
texture swizzle using the GL_ARB_texture_swizzle extension so that the
alpha component will be taken from the red component of the texture.
The swizzle is part of the texture object state so it only needs to be
set once when the texture is created.

The ‘gen’ virtual function of the texture driver has been changed to
also take the internal format as a parameter. The GL driver will now
set the swizzle as appropriate here.

The GL3 driver now reports an error if the texture swizzle extension
is not available because Cogl can't really work properly without out
it. The extension is part of GL 3.3 so it is quite likely that it has
wide support from drivers. Eventually we could get rid of this
requirement if we have our own GLSL front-end and we could generate
the swizzle ourselves.

When uploading or downloading texture data to or from a
component-alpha texture, we can no longer rely on GL to do the
conversion. The swizzle doesn't have any effect on the texture data
functions. In these cases Cogl will now force an intermediate buffer
to be used and it will manually do the conversion as it does for the
GLES drivers.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 32bacf81ebaa3be21a8f26af07d8f6eed6607652)
2013-01-22 17:48:04 +00:00

580 lines
20 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2009,2010,2011,2012 Intel Corporation.
*
* 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/>.
*
*
*
* Authors:
* Neil Roberts <neil@linux.intel.com>
* Robert Bragg <robert@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "cogl-private.h"
#include "cogl-texture-2d-gl.h"
#include "cogl-texture-2d-gl-private.h"
#include "cogl-texture-2d-private.h"
#include "cogl-pipeline-opengl-private.h"
#include "cogl-error-private.h"
void
_cogl_texture_2d_gl_free (CoglTexture2D *tex_2d)
{
if (!tex_2d->is_foreign)
_cogl_delete_gl_texture (tex_2d->gl_texture);
}
CoglBool
_cogl_texture_2d_gl_can_create (CoglContext *ctx,
int width,
int height,
CoglPixelFormat internal_format)
{
GLenum gl_intformat;
GLenum gl_format;
GLenum gl_type;
ctx->driver_vtable->pixel_format_to_gl (ctx,
internal_format,
&gl_intformat,
&gl_format,
&gl_type);
/* Check that the driver can create a texture with that size */
if (!ctx->texture_driver->size_supported (ctx,
GL_TEXTURE_2D,
gl_intformat,
gl_format,
gl_type,
width,
height))
return FALSE;
return TRUE;
}
void
_cogl_texture_2d_gl_init (CoglTexture2D *tex_2d)
{
/* We default to GL_LINEAR for both filters */
tex_2d->gl_legacy_texobj_min_filter = GL_LINEAR;
tex_2d->gl_legacy_texobj_mag_filter = GL_LINEAR;
/* Wrap mode not yet set */
tex_2d->gl_legacy_texobj_wrap_mode_s = GL_FALSE;
tex_2d->gl_legacy_texobj_wrap_mode_t = GL_FALSE;
}
CoglTexture2D *
_cogl_texture_2d_gl_new_with_size (CoglContext *ctx,
int width,
int height,
CoglPixelFormat internal_format,
CoglError **error)
{
CoglTexture2D *tex_2d;
GLenum gl_intformat;
GLenum gl_format;
GLenum gl_type;
internal_format = ctx->driver_vtable->pixel_format_to_gl (ctx,
internal_format,
&gl_intformat,
&gl_format,
&gl_type);
tex_2d = _cogl_texture_2d_create_base (ctx,
width, height,
internal_format);
tex_2d->gl_texture =
ctx->texture_driver->gen (ctx, GL_TEXTURE_2D, internal_format);
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
tex_2d->is_foreign);
GE( ctx, glTexImage2D (GL_TEXTURE_2D, 0, gl_intformat,
width, height, 0, gl_format, gl_type, NULL) );
return tex_2d;
}
CoglTexture2D *
_cogl_texture_2d_gl_new_from_bitmap (CoglBitmap *bmp,
CoglPixelFormat internal_format,
CoglError **error)
{
CoglContext *ctx = _cogl_bitmap_get_context (bmp);
CoglTexture2D *tex_2d;
CoglBitmap *dst_bmp;
GLenum gl_intformat;
GLenum gl_format;
GLenum gl_type;
uint8_t *data;
if ((dst_bmp = _cogl_texture_prepare_for_upload (bmp,
internal_format,
&internal_format,
&gl_intformat,
&gl_format,
&gl_type)) == NULL)
{
_cogl_set_error (error, COGL_TEXTURE_ERROR,
COGL_TEXTURE_ERROR_FORMAT,
"Failed to prepare texture upload due to format");
return NULL;
}
tex_2d = _cogl_texture_2d_create_base (ctx,
cogl_bitmap_get_width (bmp),
cogl_bitmap_get_height (bmp),
internal_format);
/* Keep a copy of the first pixel so that if glGenerateMipmap isn't
supported we can fallback to using GL_GENERATE_MIPMAP */
if (!cogl_has_feature (ctx, COGL_FEATURE_ID_OFFSCREEN) &&
(data = _cogl_bitmap_map (dst_bmp,
COGL_BUFFER_ACCESS_READ, 0)))
{
CoglPixelFormat format = cogl_bitmap_get_format (dst_bmp);
tex_2d->first_pixel.gl_format = gl_format;
tex_2d->first_pixel.gl_type = gl_type;
memcpy (tex_2d->first_pixel.data, data,
_cogl_pixel_format_get_bytes_per_pixel (format));
_cogl_bitmap_unmap (dst_bmp);
}
tex_2d->gl_texture =
ctx->texture_driver->gen (ctx, GL_TEXTURE_2D, internal_format);
ctx->texture_driver->upload_to_gl (ctx,
GL_TEXTURE_2D,
tex_2d->gl_texture,
FALSE,
dst_bmp,
gl_intformat,
gl_format,
gl_type);
tex_2d->gl_format = gl_intformat;
cogl_object_unref (dst_bmp);
return tex_2d;
}
#if defined (COGL_HAS_EGL_SUPPORT) && defined (EGL_KHR_image_base)
CoglTexture2D *
_cogl_egl_texture_2d_gl_new_from_image (CoglContext *ctx,
int width,
int height,
CoglPixelFormat format,
EGLImageKHR image,
CoglError **error)
{
CoglTexture2D *tex_2d;
GLenum gl_error;
tex_2d = _cogl_texture_2d_create_base (ctx,
width, height,
format);
tex_2d->gl_texture =
ctx->texture_driver->gen (ctx, GL_TEXTURE_2D, format);
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
FALSE);
while ((gl_error = ctx->glGetError ()) != GL_NO_ERROR)
;
ctx->glEGLImageTargetTexture2D (GL_TEXTURE_2D, image);
if (ctx->glGetError () != GL_NO_ERROR)
{
_cogl_set_error (error,
COGL_TEXTURE_ERROR,
COGL_TEXTURE_ERROR_BAD_PARAMETER,
"Could not create a CoglTexture2D from a given "
"EGLImage");
return NULL;
}
return tex_2d;
}
#endif
void
_cogl_texture_2d_gl_flush_legacy_texobj_filters (CoglTexture *tex,
GLenum min_filter,
GLenum mag_filter)
{
CoglTexture2D *tex_2d = COGL_TEXTURE_2D (tex);
CoglContext *ctx = tex->context;
if (min_filter == tex_2d->gl_legacy_texobj_min_filter
&& mag_filter == tex_2d->gl_legacy_texobj_mag_filter)
return;
/* Store new values */
tex_2d->gl_legacy_texobj_min_filter = min_filter;
tex_2d->gl_legacy_texobj_mag_filter = mag_filter;
/* Apply new filters to the texture */
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
tex_2d->is_foreign);
GE( ctx, glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, mag_filter) );
GE( ctx, glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, min_filter) );
}
void
_cogl_texture_2d_gl_flush_legacy_texobj_wrap_modes (CoglTexture *tex,
GLenum wrap_mode_s,
GLenum wrap_mode_t,
GLenum wrap_mode_p)
{
CoglTexture2D *tex_2d = COGL_TEXTURE_2D (tex);
CoglContext *ctx = tex->context;
/* Only set the wrap mode if it's different from the current value
to avoid too many GL calls. Texture 2D doesn't make use of the r
coordinate so we can ignore its wrap mode */
if (tex_2d->gl_legacy_texobj_wrap_mode_s != wrap_mode_s ||
tex_2d->gl_legacy_texobj_wrap_mode_t != wrap_mode_t)
{
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
tex_2d->is_foreign);
GE( ctx, glTexParameteri (GL_TEXTURE_2D,
GL_TEXTURE_WRAP_S,
wrap_mode_s) );
GE( ctx, glTexParameteri (GL_TEXTURE_2D,
GL_TEXTURE_WRAP_T,
wrap_mode_t) );
tex_2d->gl_legacy_texobj_wrap_mode_s = wrap_mode_s;
tex_2d->gl_legacy_texobj_wrap_mode_t = wrap_mode_t;
}
}
CoglTexture2D *
cogl_texture_2d_new_from_foreign (CoglContext *ctx,
unsigned int gl_handle,
int width,
int height,
CoglPixelFormat format,
CoglError **error)
{
/* NOTE: width, height and internal format are not queriable
* in GLES, hence such a function prototype.
*/
GLenum gl_error = 0;
GLint gl_compressed = GL_FALSE;
GLenum gl_int_format = 0;
CoglTexture2D *tex_2d;
/* Assert it is a valid GL texture object */
g_return_val_if_fail (ctx->glIsTexture (gl_handle), NULL);
if (!ctx->texture_driver->allows_foreign_gl_target (ctx, GL_TEXTURE_2D))
{
_cogl_set_error (error,
COGL_SYSTEM_ERROR,
COGL_SYSTEM_ERROR_UNSUPPORTED,
"Foreign GL_TEXTURE_2D textures are not "
"supported by your system");
return NULL;
}
/* Make sure binding succeeds */
while ((gl_error = ctx->glGetError ()) != GL_NO_ERROR)
;
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D, gl_handle, TRUE);
if (ctx->glGetError () != GL_NO_ERROR)
{
_cogl_set_error (error,
COGL_SYSTEM_ERROR,
COGL_SYSTEM_ERROR_UNSUPPORTED,
"Failed to bind foreign GL_TEXTURE_2D texture");
return NULL;
}
/* Obtain texture parameters
(only level 0 we are interested in) */
#if HAVE_COGL_GL
if ((ctx->private_feature_flags &
COGL_PRIVATE_FEATURE_QUERY_TEXTURE_PARAMETERS))
{
GE( ctx, glGetTexLevelParameteriv (GL_TEXTURE_2D, 0,
GL_TEXTURE_COMPRESSED,
&gl_compressed) );
{
GLint val;
GE( ctx, glGetTexLevelParameteriv (GL_TEXTURE_2D, 0,
GL_TEXTURE_INTERNAL_FORMAT,
&val) );
gl_int_format = val;
}
/* If we can query GL for the actual pixel format then we'll ignore
the passed in format and use that. */
if (!ctx->driver_vtable->pixel_format_from_gl_internal (ctx,
gl_int_format,
&format))
{
_cogl_set_error (error,
COGL_SYSTEM_ERROR,
COGL_SYSTEM_ERROR_UNSUPPORTED,
"Unsupported internal format for foreign texture");
return NULL;
}
}
else
#endif
{
/* Otherwise we'll assume we can derive the GL format from the
passed in format */
ctx->driver_vtable->pixel_format_to_gl (ctx,
format,
&gl_int_format,
NULL,
NULL);
}
/* Note: We always trust the given width and height without querying
* the texture object because the user may be creating a Cogl
* texture for a texture_from_pixmap object where glTexImage2D may
* not have been called and the texture_from_pixmap spec doesn't
* clarify that it is reliable to query back the size from OpenGL.
*/
/* Validate width and height */
g_return_val_if_fail (width > 0 && height > 0, NULL);
/* Compressed texture images not supported */
if (gl_compressed == GL_TRUE)
{
_cogl_set_error (error,
COGL_SYSTEM_ERROR,
COGL_SYSTEM_ERROR_UNSUPPORTED,
"Compressed foreign textures aren't currently supported");
return NULL;
}
/* Note: previously this code would query the texture object for
whether it has GL_GENERATE_MIPMAP enabled to determine whether to
auto-generate the mipmap. This doesn't make much sense any more
since Cogl switch to using glGenerateMipmap. Ideally I think
cogl_texture_2d_new_from_foreign should take a flags parameter so
that the application can decide whether it wants
auto-mipmapping. To be compatible with existing code, Cogl now
disables its own auto-mipmapping but leaves the value of
GL_GENERATE_MIPMAP alone so that it would still work but without
the dirtiness tracking that Cogl would do. */
/* Create new texture */
tex_2d = _cogl_texture_2d_create_base (ctx,
width, height,
format);
_cogl_texture_2d_set_auto_mipmap (COGL_TEXTURE (tex_2d), FALSE);
/* Setup bitmap info */
tex_2d->is_foreign = TRUE;
tex_2d->mipmaps_dirty = TRUE;
tex_2d->format = format;
tex_2d->gl_texture = gl_handle;
tex_2d->gl_format = gl_int_format;
/* Unknown filter */
tex_2d->gl_legacy_texobj_min_filter = GL_FALSE;
tex_2d->gl_legacy_texobj_mag_filter = GL_FALSE;
return tex_2d;
}
void
_cogl_texture_2d_gl_copy_from_framebuffer (CoglTexture2D *tex_2d,
CoglFramebuffer *src_fb,
int dst_x,
int dst_y,
int src_x,
int src_y,
int width,
int height)
{
CoglContext *ctx = COGL_TEXTURE (tex_2d)->context;
/* Make sure the current framebuffers are bound, though we don't need to
* flush the clip state here since we aren't going to draw to the
* framebuffer. */
_cogl_framebuffer_flush_state (cogl_get_draw_framebuffer (),
src_fb,
COGL_FRAMEBUFFER_STATE_ALL &
~COGL_FRAMEBUFFER_STATE_CLIP);
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
tex_2d->is_foreign);
ctx->glCopyTexSubImage2D (GL_TEXTURE_2D,
0, /* level */
dst_x, dst_y,
src_x, src_y,
width, height);
}
unsigned int
_cogl_texture_2d_gl_get_gl_handle (CoglTexture2D *tex_2d)
{
return tex_2d->gl_texture;
}
void
_cogl_texture_2d_gl_generate_mipmap (CoglTexture2D *tex_2d)
{
CoglContext *ctx = COGL_TEXTURE (tex_2d)->context;
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
tex_2d->is_foreign);
/* glGenerateMipmap is defined in the FBO extension. If it's not
available we'll fallback to temporarily enabling
GL_GENERATE_MIPMAP and reuploading the first pixel */
if (cogl_has_feature (ctx, COGL_FEATURE_ID_OFFSCREEN))
ctx->texture_driver->gl_generate_mipmaps (ctx, GL_TEXTURE_2D);
#if defined(HAVE_COGL_GLES) || defined(HAVE_COGL_GL)
else
{
GE( ctx, glTexParameteri (GL_TEXTURE_2D,
GL_GENERATE_MIPMAP,
GL_TRUE) );
GE( ctx, glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, 1, 1,
tex_2d->first_pixel.gl_format,
tex_2d->first_pixel.gl_type,
tex_2d->first_pixel.data) );
GE( ctx, glTexParameteri (GL_TEXTURE_2D,
GL_GENERATE_MIPMAP,
GL_FALSE) );
}
#endif
}
void
_cogl_texture_2d_gl_copy_from_bitmap (CoglTexture2D *tex_2d,
CoglBitmap *bmp,
int dst_x,
int dst_y,
int src_x,
int src_y,
int width,
int height)
{
CoglTexture *tex = COGL_TEXTURE (tex_2d);
CoglContext *ctx = tex->context;
GLenum gl_format;
GLenum gl_type;
uint8_t *data;
bmp = _cogl_texture_prepare_for_upload (bmp,
cogl_texture_get_format (tex),
NULL,
NULL,
&gl_format,
&gl_type);
/* If this touches the first pixel then we'll update our copy */
if (dst_x == 0 && dst_y == 0 &&
!cogl_has_feature (ctx, COGL_FEATURE_ID_OFFSCREEN) &&
(data = _cogl_bitmap_map (bmp, COGL_BUFFER_ACCESS_READ, 0)))
{
CoglPixelFormat bpp =
_cogl_pixel_format_get_bytes_per_pixel (cogl_bitmap_get_format (bmp));
tex_2d->first_pixel.gl_format = gl_format;
tex_2d->first_pixel.gl_type = gl_type;
memcpy (tex_2d->first_pixel.data,
data + cogl_bitmap_get_rowstride (bmp) * src_y + bpp * src_x,
bpp);
_cogl_bitmap_unmap (bmp);
}
/* Send data to GL */
ctx->texture_driver->upload_subregion_to_gl (ctx,
GL_TEXTURE_2D,
tex_2d->gl_texture,
FALSE,
src_x, src_y,
dst_x, dst_y,
width, height,
bmp,
gl_format,
gl_type);
cogl_object_unref (bmp);
}
void
_cogl_texture_2d_gl_get_data (CoglTexture2D *tex_2d,
CoglPixelFormat format,
int rowstride,
uint8_t *data)
{
CoglContext *ctx = COGL_TEXTURE (tex_2d)->context;
int bpp;
GLenum gl_format;
GLenum gl_type;
bpp = _cogl_pixel_format_get_bytes_per_pixel (format);
ctx->driver_vtable->pixel_format_to_gl (ctx,
format,
NULL, /* internal format */
&gl_format,
&gl_type);
ctx->texture_driver->prep_gl_for_pixels_download (ctx,
rowstride,
tex_2d->width,
bpp);
_cogl_bind_gl_texture_transient (GL_TEXTURE_2D,
tex_2d->gl_texture,
tex_2d->is_foreign);
ctx->texture_driver->gl_get_tex_image (ctx,
GL_TEXTURE_2D,
gl_format,
gl_type,
data);
}