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-rw-r--r--src/mesa/main/image.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/src/mesa/main/image.c b/src/mesa/main/image.c
index d77c593ac7..baecbab0a3 100644
--- a/src/mesa/main/image.c
+++ b/src/mesa/main/image.c
@@ -689,6 +689,22 @@ _mesa_is_depth_format(GLenum format)
/**
+ * Test if the given image format is a stencil format.
+ */
+GLboolean
+_mesa_is_stencil_format(GLenum format)
+{
+ switch (format) {
+ case GL_STENCIL_INDEX:
+ case GL_DEPTH_STENCIL:
+ return GL_TRUE;
+ default:
+ return GL_FALSE;
+ }
+}
+
+
+/**
* Test if the given image format is a YCbCr format.
*/
GLboolean
@@ -1243,6 +1259,91 @@ _mesa_pack_bitmap( GLint width, GLint height, const GLubyte *source,
}
+/**
+ * "Expand" a bitmap from 1-bit per pixel to 8-bits per pixel.
+ * This is typically used to convert a bitmap into a GLubyte/pixel texture.
+ * "On" bits will set texels to \p onValue.
+ * "Off" bits will not modify texels.
+ * \param width src bitmap width in pixels
+ * \param height src bitmap height in pixels
+ * \param unpack bitmap unpacking state
+ * \param bitmap the src bitmap data
+ * \param destBuffer start of dest buffer
+ * \param destStride row stride in dest buffer
+ * \param onValue if bit is 1, set destBuffer pixel to this value
+ */
+void
+_mesa_expand_bitmap(GLsizei width, GLsizei height,
+ const struct gl_pixelstore_attrib *unpack,
+ const GLubyte *bitmap,
+ GLubyte *destBuffer, GLint destStride,
+ GLubyte onValue)
+{
+ const GLubyte *srcRow = (const GLubyte *)
+ _mesa_image_address2d(unpack, bitmap, width, height,
+ GL_COLOR_INDEX, GL_BITMAP, 0, 0);
+ const GLint srcStride = _mesa_image_row_stride(unpack, width,
+ GL_COLOR_INDEX, GL_BITMAP);
+ GLint row, col;
+
+#define SET_PIXEL(COL, ROW) \
+ destBuffer[(ROW) * destStride + (COL)] = onValue;
+
+ for (row = 0; row < height; row++) {
+ const GLubyte *src = srcRow;
+
+ if (unpack->LsbFirst) {
+ /* Lsb first */
+ GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
+ for (col = 0; col < width; col++) {
+
+ if (*src & mask) {
+ SET_PIXEL(col, row);
+ }
+
+ if (mask == 128U) {
+ src++;
+ mask = 1U;
+ }
+ else {
+ mask = mask << 1;
+ }
+ }
+
+ /* get ready for next row */
+ if (mask != 1)
+ src++;
+ }
+ else {
+ /* Msb first */
+ GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
+ for (col = 0; col < width; col++) {
+
+ if (*src & mask) {
+ SET_PIXEL(col, row);
+ }
+
+ if (mask == 1U) {
+ src++;
+ mask = 128U;
+ }
+ else {
+ mask = mask >> 1;
+ }
+ }
+
+ /* get ready for next row */
+ if (mask != 128)
+ src++;
+ }
+
+ srcRow += srcStride;
+ } /* row */
+
+#undef SET_PIXEL
+}
+
+
/**********************************************************************/
/***** Pixel processing functions ******/
/**********************************************************************/