+#endif /* _HAVE_FULL_GL */
+
+
+
+/**
+ * Convert an array of RGBA colors from one datatype to another.
+ * NOTE: src may equal dst. In that case, we use a temporary buffer.
+ */
+void
+_mesa_convert_colors(GLenum srcType, const GLvoid *src,
+ GLenum dstType, GLvoid *dst,
+ GLuint count, const GLubyte mask[])
+{
+ GLuint tempBuffer[MAX_WIDTH][4];
+ const GLboolean useTemp = (src == dst);
+
+ ASSERT(srcType != dstType);
+
+ switch (srcType) {
+ case GL_UNSIGNED_BYTE:
+ if (dstType == GL_UNSIGNED_SHORT) {
+ const GLubyte (*src1)[4] = (const GLubyte (*)[4]) src;
+ GLushort (*dst2)[4] = (GLushort (*)[4]) (useTemp ? tempBuffer : dst);
+ GLuint i;
+ for (i = 0; i < count; i++) {
+ if (!mask || mask[i]) {
+ dst2[i][RCOMP] = UBYTE_TO_USHORT(src1[i][RCOMP]);
+ dst2[i][GCOMP] = UBYTE_TO_USHORT(src1[i][GCOMP]);
+ dst2[i][BCOMP] = UBYTE_TO_USHORT(src1[i][BCOMP]);
+ dst2[i][ACOMP] = UBYTE_TO_USHORT(src1[i][ACOMP]);
+ }
+ }
+ if (useTemp)
+ _mesa_memcpy(dst, tempBuffer, count * 4 * sizeof(GLushort));
+ }
+ else {
+ const GLubyte (*src1)[4] = (const GLubyte (*)[4]) src;
+ GLfloat (*dst4)[4] = (GLfloat (*)[4]) (useTemp ? tempBuffer : dst);
+ GLuint i;
+ ASSERT(dstType == GL_FLOAT);
+ for (i = 0; i < count; i++) {
+ if (!mask || mask[i]) {
+ dst4[i][RCOMP] = UBYTE_TO_FLOAT(src1[i][RCOMP]);
+ dst4[i][GCOMP] = UBYTE_TO_FLOAT(src1[i][GCOMP]);
+ dst4[i][BCOMP] = UBYTE_TO_FLOAT(src1[i][BCOMP]);
+ dst4[i][ACOMP] = UBYTE_TO_FLOAT(src1[i][ACOMP]);
+ }
+ }
+ if (useTemp)
+ _mesa_memcpy(dst, tempBuffer, count * 4 * sizeof(GLfloat));
+ }
+ break;
+ case GL_UNSIGNED_SHORT:
+ if (dstType == GL_UNSIGNED_BYTE) {
+ const GLushort (*src2)[4] = (const GLushort (*)[4]) src;
+ GLubyte (*dst1)[4] = (GLubyte (*)[4]) (useTemp ? tempBuffer : dst);
+ GLuint i;
+ for (i = 0; i < count; i++) {
+ if (!mask || mask[i]) {
+ dst1[i][RCOMP] = USHORT_TO_UBYTE(src2[i][RCOMP]);
+ dst1[i][GCOMP] = USHORT_TO_UBYTE(src2[i][GCOMP]);
+ dst1[i][BCOMP] = USHORT_TO_UBYTE(src2[i][BCOMP]);
+ dst1[i][ACOMP] = USHORT_TO_UBYTE(src2[i][ACOMP]);
+ }
+ }
+ if (useTemp)
+ _mesa_memcpy(dst, tempBuffer, count * 4 * sizeof(GLubyte));
+ }
+ else {
+ const GLushort (*src2)[4] = (const GLushort (*)[4]) src;
+ GLfloat (*dst4)[4] = (GLfloat (*)[4]) (useTemp ? tempBuffer : dst);
+ GLuint i;
+ ASSERT(dstType == GL_FLOAT);
+ for (i = 0; i < count; i++) {
+ if (!mask || mask[i]) {
+ dst4[i][RCOMP] = USHORT_TO_FLOAT(src2[i][RCOMP]);
+ dst4[i][GCOMP] = USHORT_TO_FLOAT(src2[i][GCOMP]);
+ dst4[i][BCOMP] = USHORT_TO_FLOAT(src2[i][BCOMP]);
+ dst4[i][ACOMP] = USHORT_TO_FLOAT(src2[i][ACOMP]);
+ }
+ }
+ if (useTemp)
+ _mesa_memcpy(dst, tempBuffer, count * 4 * sizeof(GLfloat));
+ }
+ break;
+ case GL_FLOAT:
+ if (dstType == GL_UNSIGNED_BYTE) {
+ const GLfloat (*src4)[4] = (const GLfloat (*)[4]) src;
+ GLubyte (*dst1)[4] = (GLubyte (*)[4]) (useTemp ? tempBuffer : dst);
+ GLuint i;
+ for (i = 0; i < count; i++) {
+ if (!mask || mask[i]) {
+ UNCLAMPED_FLOAT_TO_UBYTE(dst1[i][RCOMP], src4[i][RCOMP]);
+ UNCLAMPED_FLOAT_TO_UBYTE(dst1[i][GCOMP], src4[i][GCOMP]);
+ UNCLAMPED_FLOAT_TO_UBYTE(dst1[i][BCOMP], src4[i][BCOMP]);
+ UNCLAMPED_FLOAT_TO_UBYTE(dst1[i][ACOMP], src4[i][ACOMP]);
+ }
+ }
+ if (useTemp)
+ _mesa_memcpy(dst, tempBuffer, count * 4 * sizeof(GLubyte));
+ }
+ else {
+ const GLfloat (*src4)[4] = (const GLfloat (*)[4]) src;
+ GLushort (*dst2)[4] = (GLushort (*)[4]) (useTemp ? tempBuffer : dst);
+ GLuint i;
+ ASSERT(dstType == GL_UNSIGNED_SHORT);
+ for (i = 0; i < count; i++) {
+ if (!mask || mask[i]) {
+ UNCLAMPED_FLOAT_TO_USHORT(dst2[i][RCOMP], src4[i][RCOMP]);
+ UNCLAMPED_FLOAT_TO_USHORT(dst2[i][GCOMP], src4[i][GCOMP]);
+ UNCLAMPED_FLOAT_TO_USHORT(dst2[i][BCOMP], src4[i][BCOMP]);
+ UNCLAMPED_FLOAT_TO_USHORT(dst2[i][ACOMP], src4[i][ACOMP]);
+ }
+ }
+ if (useTemp)
+ _mesa_memcpy(dst, tempBuffer, count * 4 * sizeof(GLushort));
+ }
+ break;
+ default:
+ _mesa_problem(NULL, "Invalid datatype in _mesa_convert_colors");
+ }
+}
+
+
+
+
+/**
+ * Perform basic clipping for glDrawPixels. The image's position and size
+ * and the unpack SkipPixels and SkipRows are adjusted so that the image
+ * region is entirely within the window and scissor bounds.
+ * NOTE: this will only work when glPixelZoom is (1, 1) or (1, -1).
+ * If Pixel.ZoomY is -1, *destY will be changed to be the first row which
+ * we'll actually write. Beforehand, *destY-1 is the first drawing row.
+ *
+ * \return GL_TRUE if image is ready for drawing or
+ * GL_FALSE if image was completely clipped away (draw nothing)
+ */
+GLboolean
+_mesa_clip_drawpixels(const GLcontext *ctx,
+ GLint *destX, GLint *destY,
+ GLsizei *width, GLsizei *height,
+ struct gl_pixelstore_attrib *unpack)
+{
+ const GLframebuffer *buffer = ctx->DrawBuffer;
+
+ if (unpack->RowLength == 0) {
+ unpack->RowLength = *width;
+ }
+
+ ASSERT(ctx->Pixel.ZoomX == 1.0F);
+ ASSERT(ctx->Pixel.ZoomY == 1.0F || ctx->Pixel.ZoomY == -1.0F);
+
+ /* left clipping */
+ if (*destX < buffer->_Xmin) {
+ unpack->SkipPixels += (buffer->_Xmin - *destX);
+ *width -= (buffer->_Xmin - *destX);
+ *destX = buffer->_Xmin;
+ }
+ /* right clipping */
+ if (*destX + *width > buffer->_Xmax)
+ *width -= (*destX + *width - buffer->_Xmax);
+
+ if (*width <= 0)
+ return GL_FALSE;
+
+ if (ctx->Pixel.ZoomY == 1.0F) {
+ /* bottom clipping */
+ if (*destY < buffer->_Ymin) {
+ unpack->SkipRows += (buffer->_Ymin - *destY);
+ *height -= (buffer->_Ymin - *destY);
+ *destY = buffer->_Ymin;
+ }
+ /* top clipping */
+ if (*destY + *height > buffer->_Ymax)
+ *height -= (*destY + *height - buffer->_Ymax);
+ }
+ else { /* upside down */
+ /* top clipping */
+ if (*destY > buffer->_Ymax) {
+ unpack->SkipRows += (*destY - buffer->_Ymax);
+ *height -= (*destY - buffer->_Ymax);
+ *destY = buffer->_Ymax;
+ }
+ /* bottom clipping */
+ if (*destY - *height < buffer->_Ymin)
+ *height -= (buffer->_Ymin - (*destY - *height));
+ /* adjust destY so it's the first row to write to */
+ (*destY)--;
+ }
+
+ if (*height <= 0)
+ return GL_TRUE;
+
+ return GL_TRUE;
+}
+
+
+/**
+ * Perform clipping for glReadPixels. The image's window position
+ * and size, and the pack skipPixels, skipRows and rowLength are adjusted
+ * so that the image region is entirely within the window bounds.
+ * Note: this is different from _mesa_clip_drawpixels() in that the
+ * scissor box is ignored, and we use the bounds of the current readbuffer
+ * surface.
+ *
+ * \return GL_TRUE if image is ready for drawing or
+ * GL_FALSE if image was completely clipped away (draw nothing)
+ */
+GLboolean
+_mesa_clip_readpixels(const GLcontext *ctx,
+ GLint *srcX, GLint *srcY,
+ GLsizei *width, GLsizei *height,
+ struct gl_pixelstore_attrib *pack)
+{
+ const GLframebuffer *buffer = ctx->ReadBuffer;
+
+ if (pack->RowLength == 0) {
+ pack->RowLength = *width;
+ }
+
+ /* left clipping */
+ if (*srcX < 0) {
+ pack->SkipPixels += (0 - *srcX);
+ *width -= (0 - *srcX);
+ *srcX = 0;
+ }
+ /* right clipping */
+ if (*srcX + *width > (GLsizei) buffer->Width)
+ *width -= (*srcX + *width - buffer->Width);
+
+ if (*width <= 0)
+ return GL_FALSE;
+
+ /* bottom clipping */
+ if (*srcY < 0) {
+ pack->SkipRows += (0 - *srcY);
+ *height -= (0 - *srcY);
+ *srcY = 0;
+ }
+ /* top clipping */
+ if (*srcY + *height > (GLsizei) buffer->Height)
+ *height -= (*srcY + *height - buffer->Height);
+
+ if (*height <= 0)
+ return GL_TRUE;
+
+ return GL_TRUE;
+}
+
+
+/**
+ * Clip the rectangle defined by (x, y, width, height) against the bounds
+ * specified by [xmin, xmax) and [ymin, ymax).
+ * \return GL_FALSE if rect is totally clipped, GL_TRUE otherwise.
+ */
+GLboolean
+_mesa_clip_to_region(GLint xmin, GLint ymin,
+ GLint xmax, GLint ymax,
+ GLint *x, GLint *y,
+ GLsizei *width, GLsizei *height )
+{
+ /* left clipping */
+ if (*x < xmin) {
+ *width -= (xmin - *x);
+ *x = xmin;
+ }
+
+ /* right clipping */
+ if (*x + *width > xmax)
+ *width -= (*x + *width - xmax - 1);
+
+ if (*width <= 0)
+ return GL_FALSE;
+
+ /* bottom (or top) clipping */
+ if (*y < ymin) {
+ *height -= (ymin - *y);
+ *y = ymin;
+ }
+
+ /* top (or bottom) clipping */
+ if (*y + *height > ymax)
+ *height -= (*y + *height - ymax - 1);
+
+ if (*height <= 0)
+ return GL_FALSE;
+
+ return GL_TRUE;
+}