libglez/ftgl/vertex-attribute.c
2017-12-07 17:07:55 +03:00

154 lines
3.7 KiB
C

/* Freetype GL - A C OpenGL Freetype engine
*
* Distributed under the OSI-approved BSD 2-Clause License. See accompanying
* file `LICENSE` for more details.
*/
#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include "vec234.h"
#include "platform.h"
#include "vertex-attribute.h"
// ----------------------------------------------------------------------------
vertex_attribute_t *vertex_attribute_new(GLchar *name, GLint size, GLenum type,
GLboolean normalized, GLsizei stride,
GLvoid *pointer)
{
vertex_attribute_t *attribute =
(vertex_attribute_t *) malloc(sizeof(vertex_attribute_t));
assert(size > 0);
attribute->name = (GLchar *) strdup(name);
attribute->index = -1;
attribute->size = size;
attribute->type = type;
attribute->normalized = normalized;
attribute->stride = stride;
attribute->pointer = pointer;
return attribute;
}
// ----------------------------------------------------------------------------
void vertex_attribute_delete(vertex_attribute_t *self)
{
assert(self);
free(self->name);
free(self);
}
// ----------------------------------------------------------------------------
vertex_attribute_t *vertex_attribute_parse(char *format)
{
GLenum type = 0;
int size;
int normalized = 0;
char ctype;
char *name;
vertex_attribute_t *attr;
char *p = strchr(format, ':');
if (p != NULL)
{
name = strndup(format, p - format);
if (*(++p) == '\0')
{
fprintf(stderr, "No size specified for '%s' attribute\n", name);
free(name);
return 0;
}
size = *p - '0';
if (*(++p) == '\0')
{
fprintf(stderr, "No format specified for '%s' attribute\n", name);
free(name);
return 0;
}
ctype = *p;
if (*(++p) != '\0')
{
if (*p == 'n')
{
normalized = 1;
}
}
}
else
{
fprintf(stderr, "Vertex attribute format not understood ('%s')\n",
format);
return 0;
}
switch (ctype)
{
case 'b':
type = GL_BYTE;
break;
case 'B':
type = GL_UNSIGNED_BYTE;
break;
case 's':
type = GL_SHORT;
break;
case 'S':
type = GL_UNSIGNED_SHORT;
break;
case 'i':
type = GL_INT;
break;
case 'I':
type = GL_UNSIGNED_INT;
break;
case 'f':
type = GL_FLOAT;
break;
default:
type = 0;
break;
}
attr = vertex_attribute_new(name, size, type, normalized, 0, 0);
free(name);
return attr;
}
// ----------------------------------------------------------------------------
void vertex_attribute_enable(vertex_attribute_t *attr)
{
if (attr->index == -1)
{
GLint program;
glGetIntegerv(GL_CURRENT_PROGRAM, &program);
if (program == 0)
{
return;
}
attr->index = glGetAttribLocation(program, attr->name);
if (attr->index == -1)
{
return;
}
}
glEnableVertexAttribArray(attr->index);
switch (attr->type)
{
case GL_UNSIGNED_SHORT:
case GL_UNSIGNED_INT:
case GL_UNSIGNED_BYTE:
case GL_SHORT:
case GL_INT:
case GL_BYTE:
glVertexAttribIPointer(attr->index, attr->size, attr->type,
attr->stride, attr->pointer);
break;
default:
glVertexAttribPointer(attr->index, attr->size, attr->type,
attr->normalized, attr->stride, attr->pointer);
}
}