| // basisu_pvrtc1_4.cpp |
| // Copyright (C) 2019 Binomial LLC. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| #include "basisu_pvrtc1_4.h" |
| |
| namespace basisu |
| { |
| uint32_t pvrtc4_swizzle_uv(uint32_t width, uint32_t height, uint32_t x, uint32_t y) |
| { |
| assert((x < width) && (y < height) && basisu::is_pow2(height) && basisu::is_pow2(width)); |
| |
| uint32_t min_d = width, max_v = y; |
| if (height < width) |
| { |
| min_d = height; |
| max_v = x; |
| } |
| |
| // Interleave the XY LSB's |
| uint32_t shift_ofs = 0, swizzled = 0; |
| for (uint32_t s_bit = 1, d_bit = 1; s_bit < min_d; s_bit <<= 1, d_bit <<= 2, ++shift_ofs) |
| { |
| if (y & s_bit) swizzled |= d_bit; |
| if (x & s_bit) swizzled |= (2 * d_bit); |
| } |
| |
| max_v >>= shift_ofs; |
| |
| // OR in the rest of the bits from the largest dimension |
| swizzled |= (max_v << (2 * shift_ofs)); |
| |
| return swizzled; |
| } |
| |
| color_rgba pvrtc4_block::get_endpoint(uint32_t endpoint_index, bool unpack) const |
| { |
| assert(endpoint_index < 2); |
| const uint32_t packed = m_endpoints >> (endpoint_index * 16); |
| |
| uint32_t r, g, b, a; |
| if (packed & 0x8000) |
| { |
| // opaque 554 or 555 |
| if (!endpoint_index) |
| { |
| r = (packed >> 10) & 31; |
| g = (packed >> 5) & 31; |
| b = (packed >> 1) & 15; |
| |
| if (unpack) |
| { |
| b = (b << 1) | (b >> 3); |
| } |
| } |
| else |
| { |
| r = (packed >> 10) & 31; |
| g = (packed >> 5) & 31; |
| b = packed & 31; |
| } |
| |
| a = unpack ? 255 : 7; |
| } |
| else |
| { |
| // translucent 4433 or 4443 |
| if (!endpoint_index) |
| { |
| a = (packed >> 12) & 7; |
| r = (packed >> 8) & 15; |
| g = (packed >> 4) & 15; |
| b = (packed >> 1) & 7; |
| |
| if (unpack) |
| { |
| a = (a << 1); |
| a = (a << 4) | a; |
| |
| r = (r << 1) | (r >> 3); |
| g = (g << 1) | (g >> 3); |
| b = (b << 2) | (b >> 1); |
| } |
| } |
| else |
| { |
| a = (packed >> 12) & 7; |
| r = (packed >> 8) & 15; |
| g = (packed >> 4) & 15; |
| b = packed & 15; |
| |
| if (unpack) |
| { |
| a = (a << 1); |
| a = (a << 4) | a; |
| |
| r = (r << 1) | (r >> 3); |
| g = (g << 1) | (g >> 3); |
| b = (b << 1) | (b >> 3); |
| } |
| } |
| } |
| |
| if (unpack) |
| { |
| r = (r << 3) | (r >> 2); |
| g = (g << 3) | (g >> 2); |
| b = (b << 3) | (b >> 2); |
| } |
| |
| assert((r < 256) && (g < 256) && (b < 256) && (a < 256)); |
| |
| return color_rgba(r, g, b, a); |
| } |
| |
| color_rgba pvrtc4_block::get_endpoint_5554(uint32_t endpoint_index) const |
| { |
| assert(endpoint_index < 2); |
| const uint32_t packed = m_endpoints >> (endpoint_index * 16); |
| |
| uint32_t r, g, b, a; |
| if (packed & 0x8000) |
| { |
| // opaque 554 or 555 |
| if (!endpoint_index) |
| { |
| r = (packed >> 10) & 31; |
| g = (packed >> 5) & 31; |
| b = (packed >> 1) & 15; |
| |
| b = (b << 1) | (b >> 3); |
| } |
| else |
| { |
| r = (packed >> 10) & 31; |
| g = (packed >> 5) & 31; |
| b = packed & 31; |
| } |
| |
| a = 15; |
| } |
| else |
| { |
| // translucent 4433 or 4443 |
| if (!endpoint_index) |
| { |
| a = (packed >> 12) & 7; |
| r = (packed >> 8) & 15; |
| g = (packed >> 4) & 15; |
| b = (packed >> 1) & 7; |
| |
| a = a << 1; |
| |
| r = (r << 1) | (r >> 3); |
| g = (g << 1) | (g >> 3); |
| b = (b << 2) | (b >> 1); |
| } |
| else |
| { |
| a = (packed >> 12) & 7; |
| r = (packed >> 8) & 15; |
| g = (packed >> 4) & 15; |
| b = packed & 15; |
| |
| a = a << 1; |
| |
| r = (r << 1) | (r >> 3); |
| g = (g << 1) | (g >> 3); |
| b = (b << 1) | (b >> 3); |
| } |
| } |
| |
| assert((r < 32) && (g < 32) && (b < 32) && (a < 16)); |
| |
| return color_rgba(r, g, b, a); |
| } |
| |
| bool pvrtc4_image::get_interpolated_colors(uint32_t x, uint32_t y, color_rgba* pColors) const |
| { |
| assert((x < m_width) && (y < m_height)); |
| |
| int block_x0 = (static_cast<int>(x) - 2) >> 2; |
| int block_x1 = block_x0 + 1; |
| int block_y0 = (static_cast<int>(y) - 2) >> 2; |
| int block_y1 = block_y0 + 1; |
| if (m_wrap_addressing) |
| { |
| block_x0 = posmod(block_x0, m_block_width); |
| block_x1 = posmod(block_x1, m_block_width); |
| block_y0 = posmod(block_y0, m_block_height); |
| block_y1 = posmod(block_y1, m_block_height); |
| } |
| else |
| { |
| block_x0 = clamp<int>(block_x0, 0, m_block_width - 1); |
| block_x1 = clamp<int>(block_x1, 0, m_block_width - 1); |
| block_y0 = clamp<int>(block_y0, 0, m_block_height - 1); |
| block_y1 = clamp<int>(block_y1, 0, m_block_height - 1); |
| } |
| |
| pColors[0] = interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(0), m_blocks(block_x1, block_y0).get_endpoint_5554(0), m_blocks(block_x0, block_y1).get_endpoint_5554(0), m_blocks(block_x1, block_y1).get_endpoint_5554(0)); |
| pColors[3] = interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(1), m_blocks(block_x1, block_y0).get_endpoint_5554(1), m_blocks(block_x0, block_y1).get_endpoint_5554(1), m_blocks(block_x1, block_y1).get_endpoint_5554(1)); |
| |
| if (get_block_uses_transparent_modulation(x >> 2, y >> 2)) |
| { |
| for (uint32_t c = 0; c < 4; c++) |
| { |
| uint32_t m = (pColors[0][c] + pColors[3][c]) / 2; |
| pColors[1][c] = static_cast<uint8_t>(m); |
| pColors[2][c] = static_cast<uint8_t>(m); |
| } |
| pColors[2][3] = 0; |
| return true; |
| } |
| |
| for (uint32_t c = 0; c < 4; c++) |
| { |
| pColors[1][c] = static_cast<uint8_t>((pColors[0][c] * 5 + pColors[3][c] * 3) / 8); |
| pColors[2][c] = static_cast<uint8_t>((pColors[0][c] * 3 + pColors[3][c] * 5) / 8); |
| } |
| |
| return false; |
| } |
| |
| color_rgba pvrtc4_image::get_pixel(uint32_t x, uint32_t y, uint32_t m) const |
| { |
| assert((x < m_width) && (y < m_height)); |
| |
| int block_x0 = (static_cast<int>(x) - 2) >> 2; |
| int block_x1 = block_x0 + 1; |
| int block_y0 = (static_cast<int>(y) - 2) >> 2; |
| int block_y1 = block_y0 + 1; |
| if (m_wrap_addressing) |
| { |
| block_x0 = posmod(block_x0, m_block_width); |
| block_x1 = posmod(block_x1, m_block_width); |
| block_y0 = posmod(block_y0, m_block_height); |
| block_y1 = posmod(block_y1, m_block_height); |
| } |
| else |
| { |
| block_x0 = clamp<int>(block_x0, 0, m_block_width - 1); |
| block_x1 = clamp<int>(block_x1, 0, m_block_width - 1); |
| block_y0 = clamp<int>(block_y0, 0, m_block_height - 1); |
| block_y1 = clamp<int>(block_y1, 0, m_block_height - 1); |
| } |
| |
| if (get_block_uses_transparent_modulation(x >> 2, y >> 2)) |
| { |
| if (m == 0) |
| return interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(0), m_blocks(block_x1, block_y0).get_endpoint_5554(0), m_blocks(block_x0, block_y1).get_endpoint_5554(0), m_blocks(block_x1, block_y1).get_endpoint_5554(0)); |
| else if (m == 3) |
| return interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(1), m_blocks(block_x1, block_y0).get_endpoint_5554(1), m_blocks(block_x0, block_y1).get_endpoint_5554(1), m_blocks(block_x1, block_y1).get_endpoint_5554(1)); |
| |
| color_rgba l(interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(0), m_blocks(block_x1, block_y0).get_endpoint_5554(0), m_blocks(block_x0, block_y1).get_endpoint_5554(0), m_blocks(block_x1, block_y1).get_endpoint_5554(0))); |
| color_rgba h(interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(1), m_blocks(block_x1, block_y0).get_endpoint_5554(1), m_blocks(block_x0, block_y1).get_endpoint_5554(1), m_blocks(block_x1, block_y1).get_endpoint_5554(1))); |
| |
| return color_rgba((l[0] + h[0]) / 2, (l[1] + h[1]) / 2, (l[2] + h[2]) / 2, (m == 2) ? 0 : (l[3] + h[3]) / 2); |
| } |
| else |
| { |
| if (m == 0) |
| return interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(0), m_blocks(block_x1, block_y0).get_endpoint_5554(0), m_blocks(block_x0, block_y1).get_endpoint_5554(0), m_blocks(block_x1, block_y1).get_endpoint_5554(0)); |
| else if (m == 3) |
| return interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(1), m_blocks(block_x1, block_y0).get_endpoint_5554(1), m_blocks(block_x0, block_y1).get_endpoint_5554(1), m_blocks(block_x1, block_y1).get_endpoint_5554(1)); |
| |
| color_rgba l(interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(0), m_blocks(block_x1, block_y0).get_endpoint_5554(0), m_blocks(block_x0, block_y1).get_endpoint_5554(0), m_blocks(block_x1, block_y1).get_endpoint_5554(0))); |
| color_rgba h(interpolate(x, y, m_blocks(block_x0, block_y0).get_endpoint_5554(1), m_blocks(block_x1, block_y0).get_endpoint_5554(1), m_blocks(block_x0, block_y1).get_endpoint_5554(1), m_blocks(block_x1, block_y1).get_endpoint_5554(1))); |
| |
| if (m == 2) |
| return color_rgba((l[0] * 3 + h[0] * 5) / 8, (l[1] * 3 + h[1] * 5) / 8, (l[2] * 3 + h[2] * 5) / 8, (l[3] * 3 + h[3] * 5) / 8); |
| else |
| return color_rgba((l[0] * 5 + h[0] * 3) / 8, (l[1] * 5 + h[1] * 3) / 8, (l[2] * 5 + h[2] * 3) / 8, (l[3] * 5 + h[3] * 3) / 8); |
| } |
| } |
| |
| } // basisu |