Commit 62678530 authored by Paul Berry's avatar Paul Berry

mesa: Fix computation of default vertex attrib stride for 2_10_10_10 formats.

Previously, if the client program didn't specify a stride when setting
up a vertex attribute, we used _mesa_sizeof_type() to compute the size
of the type, and multiplied it by the number of components.

This didn't work for the 2_10_10_10 formats, since _mesa_sizeof_type()
returns -1 for those types, resulting in all kinds of havoc, since it
was causing the hardware to be programmed with a negative stride

This patch adds a new function _mesa_bytes_per_vertex_attrib(), which
is similar to the existing function _mesa_bytes_per_pixel(), but which
computes the size of a vertex attribute based on the type and the
number of formats.  For packed formats (currently only the 2_10_10_10
formats), it verifies that the number of components is correct and
returns the size of the packed format.  For unpacked formats, it
returns the size of the type times the number of components.

In addition, this patch adds an assertion so that if we ever forget to
update _mesa_bytes_per_vertex_attrib() when adding a new vertex
format, we'll see the problem quickly rather than having to debug a
subtle conformance test failure.

Fixes GLES3 conformance tests
Reviewed-by: default avatarBrian Paul <>
parent 11cea472
......@@ -307,6 +307,48 @@ _mesa_bytes_per_pixel(GLenum format, GLenum type)
* Get the number of bytes for a vertex attrib with the given number of
* components and type.
* \param comps number of components.
* \param type data type.
* \return bytes per attribute, or -1 if a bad comps/type combination was given.
_mesa_bytes_per_vertex_attrib(GLint comps, GLenum type)
switch (type) {
case GL_BYTE:
return comps * sizeof(GLubyte);
case GL_SHORT:
return comps * sizeof(GLshort);
case GL_INT:
return comps * sizeof(GLint);
case GL_FLOAT:
return comps * sizeof(GLfloat);
return comps * sizeof(GLhalfARB);
return comps * sizeof(GLdouble);
case GL_FIXED:
return comps * sizeof(GLfixed);
case GL_INT_2_10_10_10_REV:
case GL_UNSIGNED_INT_2_10_10_10_REV:
if (comps == 4)
return sizeof(GLuint);
return -1;
return -1;
* Test if the given format is an integer (non-normalized) format.
......@@ -49,6 +49,9 @@ _mesa_components_in_format( GLenum format );
extern GLint
_mesa_bytes_per_pixel( GLenum format, GLenum type );
extern GLint
_mesa_bytes_per_vertex_attrib(GLint comps, GLenum type);
extern GLboolean
_mesa_is_type_integer(GLenum type);
......@@ -251,7 +251,8 @@ update_array(struct gl_context *ctx,
elementSize = _mesa_sizeof_type(type) * size;
elementSize = _mesa_bytes_per_vertex_attrib(size, type);
assert(elementSize != -1);
array = &ctx->Array.ArrayObj->VertexAttrib[attrib];
array->Size = size;
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