diff options
Diffstat (limited to 'glsize.hpp')
| -rw-r--r-- | glsize.hpp | 55 |
1 files changed, 51 insertions, 4 deletions
@@ -364,6 +364,18 @@ __gl_format_channels(GLenum format) { } } +template<class X> +static inline bool +_is_pot(X x) { + return (x & (x - 1)) == 0; +} + +template<class X, class Y> +static inline X +_align(X x, Y y) { + return (x + (y - 1)) & (y - 1); +} + static inline size_t __gl_image_size(GLenum format, GLenum type, GLsizei width, GLsizei height, GLsizei depth) { size_t num_channels = __gl_format_channels(format); @@ -421,13 +433,48 @@ __gl_image_size(GLenum format, GLenum type, GLsizei width, GLsizei height, GLsiz break; } - /* FIXME: consider glPixelStore settings */ + GLint alignment = 4; + GLint row_length = 0; + GLint image_height = 0; + GLint skip_rows = 0; + GLint skip_pixels = 0; + GLint skip_images = 0; + + __glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment); + __glGetIntegerv(GL_UNPACK_ROW_LENGTH, &row_length); + __glGetIntegerv(GL_UNPACK_IMAGE_HEIGHT, &image_height); + __glGetIntegerv(GL_UNPACK_SKIP_ROWS, &skip_rows); + __glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &skip_pixels); + __glGetIntegerv(GL_UNPACK_SKIP_IMAGES, &skip_images); + + if (row_length <= 0) { + row_length = width; + } - size_t row_stride = (width*bits_per_pixel + 7)/8; + size_t row_stride = (row_length*bits_per_pixel + 7)/8; - size_t slice_stride = height*row_stride; + if (bits_per_pixel < alignment*8 && + (bits_per_pixel & 7) == 0 && + _is_pot(bits_per_pixel)) { + row_stride = _align(row_stride, alignment); + } - return depth*slice_stride; + if (image_height <= 0) { + image_height = height; + } + + /* XXX: GL_UNPACK_IMAGE_HEIGHT and GL_UNPACK_SKIP_IMAGES should probably + * not be considered for pixel rectangles. */ + + size_t image_stride = image_height*row_stride; + + size_t size = depth*image_stride; + + size += (skip_pixels*bits_per_pixel + 7)/8; + size += skip_rows*row_stride; + size += skip_images*image_stride; + + return size; } #define __glTexParameterfv_size __gl_param_size |