accelerants/3dfx/overlay.cpp

57 	// Note:  When allocating buffers, buffer allocation starts at the end of
58 	// video memory, and works backward to the end of the video frame buffer.
60 	// objects which are ordered by the buffer address with the first object
61 	// in the list having the highest buffer address.
77 	// Calculate required buffer size as a multiple of 1K.
80 	// If the buffer area starts at the end of the video memory, the Voodoo5
85 	// whether the Voodoo5 goes beyond the buffer area or whether this is some
87 	// buffer size solves the problem.  Thus, 16K is added to the buffer size.
96 	// the address where the buffer area will start.
103 		// buffer and the start of the previous buffer to allocate the new
104 		// buffer.
106 		addr_t currentBuffEndAddr = (addr_t)ovBuff->buffer + ovBuff->size;
108 			break;		// sufficient space for the new buffer
110 		prevBuffAddr = (addr_t)ovBuff->buffer;
119 		// thus space must be allocated between the last buffer and the end of
120 		// the video frame buffer.  Compute where current video frame buffer
122 		// the new buffer to be created.
131 					"byte buffer\n", buffSize, buffSize);
132 			return NULL;	// insufficient space for buffer
150 	ovBuff->buffer = (void*)(prevBuffAddr - buffSize);
152 		+ ((addr_t)ovBuff->buffer - si.videoMemAddr));
160 	TRACE("AllocateOverlayBuffer() allocated %ld (0x%lx) byte buffer at 0x%lx\n",
161 		buffSize, buffSize, ovBuff->buffer);
167 ReleaseOverlayBuffer(const overlay_buffer* buffer)
173 	if (buffer == NULL)
176 	// Find the buffer to be released.
182 		if (ovBuff->buffer == buffer->buffer) {
200 	return B_ERROR;		// buffer to be released not found in chain of buffers
205 GetOverlayConstraints(const display_mode* mode, const overlay_buffer* buffer,
208 	if ((mode == NULL) || (buffer == NULL) || (constraints == NULL))
215 	switch (buffer->space) {
222 				buffer->space);
231 	constraints->view.width.max = buffer->width;
232 	constraints->view.height.max = buffer->height;
293 ConfigureOverlay (overlay_token overlayToken, const overlay_buffer* buffer,
301 	if (buffer == NULL)
311 	if (!TDFX_DisplayOverlay(window, buffer, view)) {