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Diffstat (limited to 'src/devices/video/bt459.cpp')
-rw-r--r-- | src/devices/video/bt459.cpp | 742 |
1 files changed, 742 insertions, 0 deletions
diff --git a/src/devices/video/bt459.cpp b/src/devices/video/bt459.cpp new file mode 100644 index 00000000000..4bf7d4c5236 --- /dev/null +++ b/src/devices/video/bt459.cpp @@ -0,0 +1,742 @@ +// license:BSD-3-Clause +// copyright-holders:Patrick Mackinlay + +/* + * An implementation of the Brooktree Bt459 150MHz Monolithic CMOS 256x24 Color Palette RAMDAC device. + * + * The device was initially rated at 135MHz and increased to 150MHz with revision B. The revision + * register (the only software-visible change) is implemented in this emulation. + * + * Reference: http://www.bitsavers.org/components/brooktree/_dataBooks/1991_Brooktree_Product_Databook.pdf + * + * TODO + * - pixel pan and zoom + * - overlay/underlay + */ + +#include "emu.h" +#include "bt459.h" + +#include "screen.h" + +#define VERBOSE 0 +#include "logmacro.h" + +DEFINE_DEVICE_TYPE(BT459, bt459_device, "bt459", "Brooktree 150MHz Monolithic CMOS 256x24 Color Palette RAMDAC") + +DEVICE_ADDRESS_MAP_START(map, 8, bt459_device) + AM_RANGE(0x00, 0x00) AM_READWRITE(address_lo_r, address_lo_w) + AM_RANGE(0x01, 0x01) AM_READWRITE(address_hi_r, address_hi_w) + AM_RANGE(0x02, 0x02) AM_READWRITE(register_r, register_w) + AM_RANGE(0x03, 0x03) AM_READWRITE(palette_r, palette_w) +ADDRESS_MAP_END + +bt459_device::bt459_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) + : device_t(mconfig, BT459, tag, owner, clock), + device_palette_interface(mconfig, *this) +{ +} + +void bt459_device::device_start() +{ + save_item(NAME(m_address)); + save_item(NAME(m_address_rgb)); + + save_item(NAME(m_overlay_color)); + save_item(NAME(m_cursor_color)); + + save_item(NAME(m_command_0)); + save_item(NAME(m_command_1)); + save_item(NAME(m_command_2)); + save_item(NAME(m_pixel_read_mask)); + save_item(NAME(m_pixel_blink_mask)); + save_item(NAME(m_overlay_read_mask)); + save_item(NAME(m_overlay_blink_mask)); + save_item(NAME(m_interleave)); + save_item(NAME(m_test)); + save_item(NAME(m_red_signature)); + save_item(NAME(m_green_signature)); + save_item(NAME(m_blue_signature)); + save_item(NAME(m_cursor_command)); + + save_item(NAME(m_cursor_x)); + save_item(NAME(m_cursor_y)); + save_item(NAME(m_window_x)); + save_item(NAME(m_window_y)); + save_item(NAME(m_window_w)); + save_item(NAME(m_window_h)); + + save_item(NAME(m_cursor_ram)); + save_item(NAME(m_palette_ram)); + + save_item(NAME(m_blink_start)); +} + +void bt459_device::device_reset() +{ + m_blink_start = -1; +} + +/* + * To write color data, the MPU loads the address register with the address of + * the primary color palette RAM, overlay RAM or cursor color register location + * to be modified. The MPU performs three successive write cycles (8 bits each + * of red, green, and blue), using C0 and C1 to select either the primary color + * palette RAM, overlay RAM or cursor color registers. After the blue write + * cycle, the address register then increments to the next location, which the + * MPU may modify by writing another sequence of red, green and blue data. + * Reading color data is similar to writing it, except the MPU executes read + * cycles when it reads color data. + * + * When the MPU is accessing the color palette RAM, overlay RAM or cursor color + * registers, the address register increments after each blue read or write + * cycle. To keep track of the red, green and blue read/write cycles, the + * address register has two additional bits (ADDRa, ADDRb) that count modulo + * three. They are reset to zero when the MPU reads or writes the address + * register. The MPU does not have access to these bits. + */ +u8 bt459_device::get_component(rgb_t *arr, int index) +{ + switch (m_address_rgb) + { + case 0: // red component + if (!machine().side_effect_disabled()) + m_address_rgb = 1; + return (m_command_2 & CR2524) == CR2524_RED ? arr[index].g() : arr[index].r(); + + case 1: // green component + if (!machine().side_effect_disabled()) + m_address_rgb = 2; + return arr[index].g(); + + case 2: // blue component + if (!machine().side_effect_disabled()) + { + m_address_rgb = 0; + m_address = (m_address + 1) & ADDRESS_MASK; + } + return (m_command_2 & CR2524) == CR2524_BLUE ? arr[index].g() : arr[index].b(); + } + + // can't happen + return 0; +} + +void bt459_device::set_component(rgb_t *arr, int index, u8 data) +{ + switch (m_address_rgb) + { + case 0: // red component + m_address_rgb = 1; + (m_command_2 & CR2524) == CR2524_RED ? arr[index].set_g(data) : arr[index].set_r(data); + break; + + case 1: // green component + m_address_rgb = 2; + arr[index].set_g(data); + break; + + case 2: // blue component + m_address_rgb = 0; + m_address = (m_address + 1) & ADDRESS_MASK; + (m_command_2 & CR2524) == CR2524_BLUE ? arr[index].set_g(data) : arr[index].set_b(data); + break; + } +} + +READ8_MEMBER(bt459_device::address_lo_r) +{ + // reset component pointer and return address register lsb + if (!machine().side_effect_disabled()) + m_address_rgb = 0; + return m_address & ADDRESS_LSB; +} + +WRITE8_MEMBER(bt459_device::address_lo_w) +{ + // reset component pointer and set address register lsb + m_address_rgb = 0; + m_address = (m_address & ADDRESS_MSB) | data; +} + +READ8_MEMBER(bt459_device::address_hi_r) +{ + // reset component pointer and return address register msb + if (!machine().side_effect_disabled()) + m_address_rgb = 0; + return (m_address & ADDRESS_MSB) >> 8; +} + +WRITE8_MEMBER(bt459_device::address_hi_w) +{ + // reset component pointer and set address register msb + m_address_rgb = 0; + m_address = ((data << 8) | (m_address & ADDRESS_LSB)) & ADDRESS_MASK; +} + +READ8_MEMBER(bt459_device::register_r) +{ + u8 result = 0; + + switch (m_address) + { + case REG_OVERLAY_COLOR_0: + case REG_OVERLAY_COLOR_1: + case REG_OVERLAY_COLOR_2: + case REG_OVERLAY_COLOR_3: + case REG_OVERLAY_COLOR_4: + case REG_OVERLAY_COLOR_5: + case REG_OVERLAY_COLOR_6: + case REG_OVERLAY_COLOR_7: + case REG_OVERLAY_COLOR_8: + case REG_OVERLAY_COLOR_9: + case REG_OVERLAY_COLOR_10: + case REG_OVERLAY_COLOR_11: + case REG_OVERLAY_COLOR_12: + case REG_OVERLAY_COLOR_13: + case REG_OVERLAY_COLOR_14: + case REG_OVERLAY_COLOR_15: + return get_component(m_overlay_color, m_address & 0xf); + + case REG_CURSOR_COLOR_1: return get_component(m_cursor_color, 0); + case REG_CURSOR_COLOR_2: return get_component(m_cursor_color, 1); + case REG_CURSOR_COLOR_3: return get_component(m_cursor_color, 2); + + case REG_ID: + result = m_id; + LOG("id register read (%s)\n", machine().describe_context()); + break; + + case REG_COMMAND_0: result = m_command_0; break; + case REG_COMMAND_1: result = m_command_1; break; + case REG_COMMAND_2: result = m_command_2; break; + case REG_PIXEL_READ_MASK: result = m_pixel_read_mask; break; + + case REG_PIXEL_BLINK_MASK: result = m_pixel_blink_mask; break; + + case REG_OVERLAY_READ_MASK: result = m_overlay_read_mask; break; + case REG_OVERLAY_BLINK_MASK: result = m_overlay_blink_mask; break; + case REG_INTERLEAVE: result = m_interleave; break; + + case REG_TEST: result = m_test; break; + case REG_RED_SIGNATURE: result = m_red_signature; break; + case REG_GREEN_SIGNATURE: result = m_green_signature; break; + case REG_BLUE_SIGNATURE: result = m_blue_signature; break; + + case REG_REVISION: + result = m_revision; + LOG("revision register read (%s)\n", machine().describe_context()); + break; + + case REG_CURSOR_COMMAND: result = m_cursor_command; break; + + case REG_CURSOR_X_LO: result = m_cursor_x & 0xff; break; + case REG_CURSOR_X_HI: result = (m_cursor_x >> 8); break; + case REG_CURSOR_Y_LO: result = m_cursor_y & 0xff; break; + case REG_CURSOR_Y_HI: result = (m_cursor_y >> 8); break; + + case REG_WINDOW_X_LO: result = m_window_x & 0xff; break; + case REG_WINDOW_X_HI: result = (m_window_x >> 8); break; + case REG_WINDOW_Y_LO: result = m_window_y & 0xff; break; + case REG_WINDOW_Y_HI: result = (m_window_y >> 8); break; + + case REG_WINDOW_W_LO: result = m_window_w & 0xff; break; + case REG_WINDOW_W_HI: result = (m_window_w >> 8); break; + case REG_WINDOW_H_LO: result = m_window_h & 0xff; break; + case REG_WINDOW_H_HI: result = (m_window_h >> 8); break; + + default: + if (m_address >= CURSOR_RAM_START && m_address <= CURSOR_RAM_END) + result = m_cursor_ram[m_address & CURSOR_RAM_MASK]; + else + LOG("read from unknown address 0x%04x (%s)\n", m_address, machine().describe_context()); + break; + } + + // increment address register and return result + m_address = (m_address + 1) & ADDRESS_MASK; + return result; +} + +WRITE8_MEMBER(bt459_device::register_w) +{ + switch (m_address) + { + case REG_COMMAND_0: + m_command_0 = data; + LOG("command register 0: multiplex select %s, use %s, blink rate %s, block mode %d bits per pixel\n", + (data & CR0706) == CR0706_51MPX ? "5:1" : + (data & CR0706) == CR0706_11MPX ? "1:1" : + (data & CR0706) == CR0706_41MPX ? "4:1" : "reserved", + (data & CR05) ? "overlay color 0" : "color palette RAM", + (data & CR0302) == CR0302_6464 ? "64 on 64 off" : + (data & CR0302) == CR0302_3232 ? "32 on 32 off" : + (data & CR0302) == CR0302_1616 ? "16 on 16 off" : "16 on 48 off", + 8 >> (data & CR0100)); + + // reset the blink timer + m_blink_start = -1; + break; + + case REG_COMMAND_1: + m_command_1 = data; + LOG("command register 1: pan select %d pixels, zoom factor %dx\n", + (data >> 5), (data & CR1310) + 1); + break; + + case REG_COMMAND_2: + m_command_2 = data; + LOG("command register 2: %s sync, %s IRE pedestal, load palette RAM select %s, PLL select %s, %s overlays, %s cursor, %s test\n", + (data & CR27) ? "enable" : "disable", + (data & CR26) ? "7.5" : "0", + (data & CR2524) == CR2524_BLUE ? "blue RAMDAC" : + (data & CR2524) == CR2524_GREEN ? "green RAMDAC" : + (data & CR2524) == CR2524_RED ? "red RAMDAC" : "normal", + (data & CR23) ? "BLANK*" : "SYNC*", + (data & CR22) ? "X Windows" : "normal", + (data & CR21) ? "X Windows" : "normal", + (data & CR20) ? "data strobe" : "signature analysis"); + break; + + case REG_PIXEL_READ_MASK: + m_pixel_read_mask = data; + LOG("pixel read mask register: 0x%02x\n", data); + break; + + case REG_PIXEL_BLINK_MASK: + m_pixel_blink_mask = data; + LOG("pixel blink mask register: 0x%02x\n", data); + break; + + case REG_OVERLAY_READ_MASK: + m_overlay_read_mask = data; + LOG("overlay read mask register: 0x%02x\n", data); + break; + + case REG_OVERLAY_BLINK_MASK: + m_overlay_blink_mask = data; + LOG("overlay blink mask register: 0x%02x\n", data); + break; + + case REG_INTERLEAVE: + m_interleave = data; + LOG("interleave register: interleave select %d pixels, first pixel select pixel %c, overlay interleave %s, underlay %s\n", + data >> 5, + ((data & CR3432) >> 2) + 'A', + (data & CR31) ? "enabled" : "disabled", + (data & CR30) ? "enabled" : "disabled"); + break; + + case REG_TEST: + m_test = data; + LOG("test register: 0x%02x\n", data); + break; + + case REG_RED_SIGNATURE: + m_red_signature = data; + LOG("red signature register: 0x%02x\n", data); + break; + case REG_GREEN_SIGNATURE: + m_green_signature = data; + LOG("green signature register: 0x%02x\n", data); + break; + case REG_BLUE_SIGNATURE: + m_blue_signature = data; + LOG("blue signature register: 0x%02x\n", data); + break; + + case REG_CURSOR_COMMAND: + m_cursor_command = data; + LOG("cursor command register: 64x64 cursor plane1 %s, 64x64 cursor plane0 %s, cross hair cursor plane1 %s, " + "cross hair cursor plane0 %s, cursor format %s, cross hair thickness %d pixels, cursor blink %s\n", + (data & CR47) ? "enable" : "disable", + (data & CR46) ? "enable" : "disable", + (data & CR45) ? "enable" : "disable", + (data & CR44) ? "enable" : "disable", + (data & CR43) ? "OR" : "XOR", + (data & CR4241) + 1, + (data & CR40) ? "enable" : "disable" + ); + break; + + case REG_CURSOR_X_LO: + m_cursor_x = (m_cursor_x & 0x0f00) | data; + LOG("cursor x low register: 0x%02x\n", data); + break; + case REG_CURSOR_X_HI: + m_cursor_x = ((data & 0xf) << 8) | (m_cursor_x & 0xff); + LOG("cursor x high register: 0x%02x\n", data); + break; + case REG_CURSOR_Y_LO: + m_cursor_y = (m_cursor_y & 0x0f00) | data; + LOG("cursor y low register: 0x%02x\n", data); + break; + case REG_CURSOR_Y_HI: + m_cursor_y = ((data & 0xf) << 8) | (m_cursor_y & 0xff); + LOG("cursor y high register: 0x%02x\n", data); + break; + + case REG_WINDOW_X_LO: + m_window_x = (m_window_x & 0x0f00) | data; + LOG("window x low register: 0x%02x\n", data); + break; + case REG_WINDOW_X_HI: + m_window_x = ((data & 0xf) << 8) | (m_window_x & 0xff); + LOG("window x high register: 0x%02x\n", data); + break; + case REG_WINDOW_Y_LO: + m_window_y = (m_window_y & 0x0f00) | data; + LOG("window y low register: 0x%02x\n", data); + break; + case REG_WINDOW_Y_HI: + m_window_y = ((data & 0xf) << 8) | (m_window_y & 0xff); + LOG("window y high register: 0x%02x\n", data); + break; + + case REG_WINDOW_W_LO: + m_window_w = (m_window_w & 0x0f00) | data; + LOG("window width low register: 0x%02x\n", data); + break; + case REG_WINDOW_W_HI: + m_window_w = ((data & 0xf) << 8) | (m_window_w & 0xff); + LOG("window width high register: 0x%02x\n", data); + break; + case REG_WINDOW_H_LO: + m_window_h = (m_window_h & 0x0f00) | data; + LOG("window height low register: 0x%02x\n", data); + break; + case REG_WINDOW_H_HI: + m_window_h = ((data & 0xf) << 8) | (m_window_h & 0xff); + LOG("window height high register: 0x%02x\n", data); + break; + + case REG_OVERLAY_COLOR_0: + case REG_OVERLAY_COLOR_1: + case REG_OVERLAY_COLOR_2: + case REG_OVERLAY_COLOR_3: + case REG_OVERLAY_COLOR_4: + case REG_OVERLAY_COLOR_5: + case REG_OVERLAY_COLOR_6: + case REG_OVERLAY_COLOR_7: + case REG_OVERLAY_COLOR_8: + case REG_OVERLAY_COLOR_9: + case REG_OVERLAY_COLOR_10: + case REG_OVERLAY_COLOR_11: + case REG_OVERLAY_COLOR_12: + case REG_OVERLAY_COLOR_13: + case REG_OVERLAY_COLOR_14: + case REG_OVERLAY_COLOR_15: + { + const int index = m_address & 0xf; + set_component(m_overlay_color, index, data); + + // update the mame palette to match the device + if (m_address_rgb == 0) + set_pen_color(BT459_PIXEL_COLORS + index, m_overlay_color[index]); + return; + } + + case REG_CURSOR_COLOR_1: + set_component(m_cursor_color, 0, data); + + // update the mame palette to match the device + if (m_address_rgb == 0) + set_pen_color(BT459_PIXEL_COLORS + BT459_OVERLAY_COLORS + 0, m_cursor_color[0]); + return; + + case REG_CURSOR_COLOR_2: + set_component(m_cursor_color, 1, data); + + // update the mame palette to match the device + if (m_address_rgb == 0) + set_pen_color(BT459_PIXEL_COLORS + BT459_OVERLAY_COLORS + 1, m_cursor_color[1]); + return; + + case REG_CURSOR_COLOR_3: + set_component(m_cursor_color, 2, data); + + // update the mame palette to match the device + if (m_address_rgb == 0) + set_pen_color(BT459_PIXEL_COLORS + BT459_OVERLAY_COLORS + 2, m_cursor_color[2]); + return; + + default: + if (m_address >= CURSOR_RAM_START && m_address <= CURSOR_RAM_END) + m_cursor_ram[m_address & CURSOR_RAM_MASK] = data; + else + LOG("write to unknown address 0x%04x data 0x%02x (%s)\n", m_address, data, machine().describe_context()); + break; + } + + // increment address register + m_address = (m_address + 1) & ADDRESS_MASK; +} + +READ8_MEMBER(bt459_device::palette_r) +{ + // return component from palette ram + return get_component(m_palette_ram, m_address & 0xff); +} + +WRITE8_MEMBER(bt459_device::palette_w) +{ + // set component in color palette ram + const int index = m_address & 0xff; + set_component(m_palette_ram, index, data); + + // update the mame palette to match the device + if (m_address_rgb == 0) + set_pen_color(index, m_palette_ram[index]); +} + +void bt459_device::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect, u8 *pixel_data) +{ + // initialise the blink timer + if (m_blink_start > screen.frame_number()) + m_blink_start = screen.frame_number(); + + // compute the blink state according to the programmed duty cycle + const bool blink_state = ((screen.frame_number() - m_blink_start) & ( + (m_command_0 & CR0302) == CR0302_1616 ? 0x10 : + (m_command_0 & CR0302) == CR0302_3232 ? 0x20 : + (m_command_0 & CR0302) == CR0302_6464 ? 0x40 : 0x30)) == 0; + + // compute the pixel mask from the pixel read mask and blink mask/state + const u8 pixel_mask = m_pixel_read_mask & (blink_state ? 0xffU : ~m_pixel_blink_mask); + + // draw visible pixel data + switch (m_command_0 & CR0100) + { + case CR0100_1BPP: + for (int y = screen.visible_area().min_y; y <= screen.visible_area().max_y; y++) + for (int x = screen.visible_area().min_x; x <= screen.visible_area().max_x; x += 8) + { + u8 data = *pixel_data++; + + bitmap.pix(y, x + 7) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 6) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 5) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 4) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 3) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 2) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 1) = get_rgb(data & 0x1, pixel_mask); data >>= 1; + bitmap.pix(y, x + 0) = get_rgb(data & 0x1, pixel_mask); + } + break; + + case CR0100_2BPP: + for (int y = screen.visible_area().min_y; y <= screen.visible_area().max_y; y++) + for (int x = screen.visible_area().min_x; x <= screen.visible_area().max_x; x += 4) + { + u8 data = *pixel_data++; + + bitmap.pix(y, x + 3) = get_rgb(data & 0x3, pixel_mask); data >>= 2; + bitmap.pix(y, x + 2) = get_rgb(data & 0x3, pixel_mask); data >>= 2; + bitmap.pix(y, x + 1) = get_rgb(data & 0x3, pixel_mask); data >>= 2; + bitmap.pix(y, x + 0) = get_rgb(data & 0x3, pixel_mask); + } + break; + + case CR0100_4BPP: + for (int y = screen.visible_area().min_y; y <= screen.visible_area().max_y; y++) + for (int x = screen.visible_area().min_x; x <= screen.visible_area().max_x; x += 2) + { + u8 data = *pixel_data++; + + bitmap.pix(y, x + 1) = get_rgb(data & 0x7, pixel_mask); data >>= 4; + bitmap.pix(y, x + 0) = get_rgb(data & 0x7, pixel_mask); + } + break; + + case CR0100_8BPP: + for (int y = screen.visible_area().min_y; y <= screen.visible_area().max_y; y++) + for (int x = screen.visible_area().min_x; x <= screen.visible_area().max_x; x++) + bitmap.pix(y, x) = get_rgb(*pixel_data++, pixel_mask); + break; + } + + // draw cursors when visible and not blinked off + if ((m_cursor_command & (CR47 | CR46 | CR45 | CR44)) && ((m_cursor_command & CR40) == 0 || blink_state)) + { + // get 64x64 bitmap and cross hair cursor plane enable + const u8 bm_cursor_enable = (m_cursor_command & (CR47 | CR46)) >> 6; + const u8 ch_cursor_enable = (m_cursor_command & (CR45 | CR44)) >> 4; + + // get cross hair cursor half thickness + const int ch_thickness = (m_cursor_command & CR4241) >> 1; + + /* + * The cursor (x) value to be written is calculated as follows: + * + * Cx = desired display screen (x) position + H - P + * + * where + * + * P = 37 if 1:1 input multiplexing, 52 if 4:1 input multiplexing, + * 57 if 5:1 input multiplexing + * H = number of pixels between the first rising edge of LD* + * following the falling edge of HSYNC* to active video + * + * The cursor (y) value to be written is calculated as follows: + * + * Cy = desired display screen (y) position + V - 32 + * + * where + * + * V = number of scan lines from the second sync pulse during + * vertical blanking to active video + * + * Values from $0FC0 (-64) to $0FBF (+4031) may be loaded into the + * cursor (y) register. The negative values ($0FC0 to $0FFF) are used + * in situations where V < 32, and the cursor must be moved off the + * top of the screen. + */ + const int cursor_x = m_cursor_x + ( + (m_command_0 & CR0706) == CR0706_11MPX ? 37 : + (m_command_0 & CR0706) == CR0706_41MPX ? 52 : + (m_command_0 & CR0706) == CR0706_51MPX ? 57 : 0); + const int cursor_y = (m_cursor_y < 0xfc0 ? m_cursor_y : m_cursor_y - 0x1000) + 32; + + // 64x64 bitmap cursor + if (bm_cursor_enable) + { + // compute target 64x64 rectangle + rectangle cursor(cursor_x - 31, cursor_x + 32, cursor_y - 31, cursor_y + 32); + + // intersect with screen bitmap + cursor &= bitmap.cliprect(); + + // draw if any portion is visible + if (!cursor.empty()) + { + for (int y = 0; y < 64; y++) + { + // get screen y pixel coordinate + const int ypos = cursor_y - 31 + y; + + for (int x = 0; x < 64; x++) + { + // get screen x pixel coordinate + const int xpos = cursor_x - 31 + x; + + // check if pixel is visible + if (cursor.contains(xpos, ypos)) + { + // retrieve 2 bits of 64x64 bitmap cursor data + u8 data = (m_cursor_ram[y * 16 + (x >> 2)] >> ((3 - (x & 3)) << 1)) & bm_cursor_enable; + + // check for dual-cursor mode and combine with cross-hair data + if (ch_cursor_enable) + if (((x >= 31 - ch_thickness) && (x <= 31 + ch_thickness)) || ((y >= 31 - ch_thickness) && (y <= 31 + ch_thickness))) + data = (m_cursor_command & CR43) ? data | ch_cursor_enable : data ^ ch_cursor_enable; + + // write cursor data to screen (normal or X Window mode) + if (data && !((m_command_2 & CR21) && data == 1)) + bitmap.pix(ypos, xpos) = m_cursor_color[data - 1]; + } + } + } + } + } + + // cross hair cursor + if (ch_cursor_enable) + { + // get the cross hair cursor color + const rgb_t ch_color = m_cursor_color[ch_cursor_enable - 1]; + + /* + * The window (x) value to be written is calculated as follows: + * + * Wx = desired display screen (x) position + H - P + * + * where + * + * P = 5 if 1:1 input multiplexing, 20 if 4:1 input multiplexing, + * 25 if 5:1 input multiplexing + * H = number of pixels between the first rising edge of LD* + * following the falling edge of HSYNC* to active video + * + * The window (y) value to be written is calculated as follows: + * + * Wy = desired display screen (y) position + V + * + * where + * + * V = number of scan lines from the second sync pulse during + * vertical blanking to active video + * + * Values from $0000 to $0FFF may be written to the window (x) and + * (y) registers. A full-screen cross hair is implemented by + * loading the window (x,y) registers with $0000, and the window + * width and height registers with $0FFF. + */ + const bool full_screen = (m_window_x == 0 && m_window_y == 0 && m_window_w == 0x0fff && m_window_h == 0x0fff); + const int window_x = full_screen ? screen.visible_area().min_x : m_window_x + ( + (m_command_0 & CR0706) == CR0706_11MPX ? 5 : + (m_command_0 & CR0706) == CR0706_41MPX ? 20 : + (m_command_0 & CR0706) == CR0706_51MPX ? 25 : 0); + const int window_y = full_screen ? screen.visible_area().min_y : m_window_y; + + /* + * The actual window width is 2, 8 or 10 pixels more than the + * value specified by the window width register, depending on + * whether 1:1, 4:1 or 5:1 input multiplexing is specified. The + * actual window height is 2 pixels more than the value specified + * by the window height register. Therefore, the minimum window + * width is 2, 8 or 10 pixels for 1:1, 4:1 and 5:1 multiplexing, + * respectively. The minimum window height is 2 pixels. + * + * Values from $0000 to $0FFF may be written to the window width + * and height registers. + * + * Note: testing indicates the cross-hair cursor should be drawn + * strictly inside the window, although this is not 100% clear from + * the documentation. + */ + const int window_w = full_screen ? screen.visible_area().width() : m_window_w + ( + (m_command_0 & CR0706) == CR0706_11MPX ? 2 : + (m_command_0 & CR0706) == CR0706_41MPX ? 8 : + (m_command_0 & CR0706) == CR0706_51MPX ? 10 : 0); + const int window_h = full_screen ? screen.visible_area().height() : m_window_h + 2; + + // check for dual-cursor mode + if (bm_cursor_enable) + { + // draw the cross hair cursor as vertical and horizontal filled rectangles broken by the 64x64 cursor area + rectangle v1(cursor_x - ch_thickness, cursor_x + ch_thickness, window_y + 1, cursor_y - 32); + rectangle v2(cursor_x - ch_thickness, cursor_x + ch_thickness, cursor_y + 33, window_y + window_h); + rectangle h1(window_x + 1, cursor_x - 32, cursor_y - ch_thickness, cursor_y + ch_thickness); + rectangle h2(cursor_x + 33, window_x + window_w, cursor_y - ch_thickness, cursor_y + ch_thickness); + + v1 &= bitmap.cliprect(); + v2 &= bitmap.cliprect(); + h1 &= bitmap.cliprect(); + h2 &= bitmap.cliprect(); + + if (!v1.empty()) + bitmap.fill(ch_color, v1); + if (!v2.empty()) + bitmap.fill(ch_color, v2); + if (!h1.empty()) + bitmap.fill(ch_color, h1); + if (!h2.empty()) + bitmap.fill(ch_color, h2); + } + else + { + // draw the cross hair cursor as unbroken vertical and horizontal filled rectangles + rectangle v(cursor_x - ch_thickness, cursor_x + ch_thickness, window_y + 1, window_y + window_h); + rectangle h(window_x + 1, window_x + window_w, cursor_y - ch_thickness, cursor_y + ch_thickness); + + v &= bitmap.cliprect(); + h &= bitmap.cliprect(); + + if (!v.empty()) + bitmap.fill(ch_color, v); + if (!h.empty()) + bitmap.fill(ch_color, h); + } + } + } +} |