renderer/src/image_draw_attributes.hpp

#pragma once

#include <array>
#include "generated/shaders/tessellate.glsl.exports.h"

namespace rive::gpu
{
static constexpr auto ImageDrawInstanceBaseAttributes = std::array{
    VertexAttribute{
        // m_viewMatrix (2x2)
        VertexElementFormat::float4,
        ImageDrawInstanceBase::FirstAttribIdx + 0,
        0,
        GLSL_a_imageDrawViewMatrix,
    },
    VertexAttribute{
        // m_clipRectInverseMatrix (2x2)
        VertexElementFormat::float4,
        ImageDrawInstanceBase::FirstAttribIdx + 1,
        4 * sizeof(float),
        GLSL_a_imageDrawClipRectInverseMatrix,
    },
    VertexAttribute{
        // packed: m_translate (2), m_clipRectInverseTranslate(2)
        VertexElementFormat::float4,
        ImageDrawInstanceBase::FirstAttribIdx + 2,
        8 * sizeof(float),
        GLSL_a_imageDrawTranslates,
    },
    VertexAttribute{
        // m_opacity/m_modulatedColor
        VertexElementFormat::uint32,
        ImageDrawInstanceBase::FirstAttribIdx + 3,
        12 * sizeof(float),
        GLSL_a_imageDrawModulatedColor,
    },
    VertexAttribute{
        // m_clipID
        VertexElementFormat::uint32,
        ImageDrawInstanceBase::FirstAttribIdx + 4,
        13 * sizeof(float),
        GLSL_a_imageDrawClipID,
    },
    VertexAttribute{
        // m_blendMode
        VertexElementFormat::uint32,
        ImageDrawInstanceBase::FirstAttribIdx + 5,
        14 * sizeof(float),
        GLSL_a_imageDrawBlendMode,
    },
    VertexAttribute{
        // m_zIndex
        VertexElementFormat::uint32,
        ImageDrawInstanceBase::FirstAttribIdx + 6,
        15 * sizeof(float),
        GLSL_a_imageDrawZIndex,
    },
};

static_assert(
    std::size(ImageDrawInstanceBaseAttributes) ==
    ImageDrawInstanceBase::AttributeCount);
static_assert(
    std::size(ImageDrawInstanceBaseAttributes) == IMAGE_COMMON_ATTRIB_COUNT);

static constexpr auto ImageRectInstanceAttributes = std::apply(
    [](auto... baseAttribs) {
      constexpr auto BaseIndex = ImageDrawInstanceBase::LastAttribIdx + 1;
      return std::array{
          baseAttribs..., // ImageDrawInstanceBase attributes come first
          VertexAttribute{
              // m_imageMatrix
              VertexElementFormat::float4,
              BaseIndex + 0,
              16 * sizeof(float),
              GLSL_a_imageRectImageMatrix,
          },
          VertexAttribute{
              // m_gradientMatrix
              VertexElementFormat::float4,
              BaseIndex + 1,
              20 * sizeof(float),
              GLSL_a_imageRectGradientMatrix,
          },
          VertexAttribute{
              // packed: m_imageTranslate and m_gradientTranslate
              VertexElementFormat::float4,
              BaseIndex + 2,
              24 * sizeof(float),
              GLSL_a_imageRectImageAndGradientTranslates,
          },
          VertexAttribute{// packed: m_gradTextureHorizontalSpan,
                          // m_gradTextureY, m_gradientType
                          VertexElementFormat::float4,
                          BaseIndex + 3,
                          28 * sizeof(float),
                          GLSL_a_imageRectPackedGradientData},
      };
    },
    ImageDrawInstanceBaseAttributes);

static_assert(
    std::size(ImageRectInstanceAttributes) == IMAGE_RECT_ATTRIB_COUNT);

static constexpr auto ImageMeshInstanceAttributes = std::apply(
    [](auto... baseAttribs) {
      constexpr auto BaseIndex = ImageDrawInstanceBase::LastAttribIdx + 1;
      return std::array{
          baseAttribs..., // ImageDrawInstanceBase attributes come first
          VertexAttribute{
              // packed: m_uvTranslate (x,y), m_uvScale (x,y)
              VertexElementFormat::float4,
              BaseIndex + 0,
              16 * sizeof(float),
              GLSL_a_imageMeshUVTransform,
          },
      };
    },
    ImageDrawInstanceBaseAttributes);

static_assert(
    std::size(ImageMeshInstanceAttributes) == IMAGE_MESH_ATTRIB_COUNT);

} // namespace rive::gpu