LibSoftGPU: Add Image class

This serves as the storage for all image types. 1D, 2D, 3D, Cube and
image arrays.

Upon construction a full mipmap chain is generated and the image is
immutable afterwards with respect to its layout.

1 files changed, 68 insertions, 0 deletions

diff --git a/Userland/Libraries/LibSoftGPU/Image.h b/Userland/Libraries/LibSoftGPU/Image.h
new file mode 100644
index 0000000000..f46d3f601c
--- /dev/null
+++ b/Userland/Libraries/LibSoftGPU/Image.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2021, Stephan Unverwerth <s.unverwerth@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <AK/Vector.h>
+#include <LibGfx/Vector3.h>
+#include <LibGfx/Vector4.h>
+#include <LibSoftGPU/ImageFormat.h>
+
+namespace SoftGPU {
+
+class Image final : public RefCounted<Image> {
+public:
+    Image(ImageFormat format, unsigned width, unsigned height, unsigned depth, unsigned levels, unsigned layers);
+
+    ImageFormat format() const { return m_format; }
+    unsigned width() const { return m_width; }
+    unsigned height() const { return m_height; }
+    unsigned depth() const { return m_depth; }
+    unsigned level_width(unsigned level) const { return m_mipmap_sizes[level].x(); }
+    unsigned level_height(unsigned level) const { return m_mipmap_sizes[level].y(); }
+    unsigned level_depth(unsigned level) const { return m_mipmap_sizes[level].z(); }
+    unsigned num_levels() const { return m_num_levels; }
+    unsigned num_layers() const { return m_num_layers; }
+
+    FloatVector4 texel(unsigned layer, unsigned level, unsigned x, unsigned y, unsigned z) const
+    {
+        return unpack_color(texel_pointer(layer, level, x, y, z), m_format);
+    }
+
+    void set_texel(unsigned layer, unsigned level, unsigned x, unsigned y, unsigned z, FloatVector4 const& color)
+    {
+        pack_color(color, texel_pointer(layer, level, x, y, z), m_format);
+    }
+
+private:
+    void const* texel_pointer(unsigned layer, unsigned level, unsigned x, unsigned y, unsigned z) const
+    {
+        auto size = m_mipmap_sizes[level];
+        return &m_data[m_mipchain_size * layer + m_mipmap_offsets[level] + (z * size.x() * size.y() + y * size.x() + x) * element_size(m_format)];
+    }
+
+    void* texel_pointer(unsigned layer, unsigned level, unsigned x, unsigned y, unsigned z)
+    {
+        auto size = m_mipmap_sizes[level];
+        return &m_data[m_mipchain_size * layer + m_mipmap_offsets[level] + (z * size.x() * size.y() + y * size.x() + x) * element_size(m_format)];
+    }
+
+private:
+    ImageFormat m_format { ImageFormat::RGBA8888 };
+    unsigned m_width { 0 };
+    unsigned m_height { 0 };
+    unsigned m_depth { 0 };
+    unsigned m_num_levels { 0 };
+    unsigned m_num_layers { 0 };
+
+    size_t m_mipchain_size { 0 };
+    Vector<size_t, 16> m_mipmap_offsets;
+    Vector<Vector3<unsigned>, 16> m_mipmap_sizes;
+    Vector<u8> m_data;
+};
+
+}