Cleanup: Move remaining GPU headers to C++

Pull Request: https://projects.blender.org/blender/blender/pulls/119807

source/blender/gpu/GPU_shader_builtin.hh

@@ -0,0 +1,145 @@
+/* SPDX-FileCopyrightText: 2023 Blender Authors
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+/** \file
+ * \ingroup gpu
+ *
+ * Set of shaders used for interface drawing.
+ *
+ * 2D shaders are not expected to work in 3D.
+ * 3D shaders can work with 2D geometry and matrices.
+ *
+ * `INST` suffix means instance, which means the shader is build to leverage instancing
+ * capabilities to reduce the number of draw-calls.
+ *
+ * For full list of parameters, search for the associated #ShaderCreateInfo.
+ * Example: `GPU_SHADER_ICON` is defined by `GPU_SHADER_CREATE_INFO(gpu_shader_icon)`
+ * Some parameters are builtins and are set automatically (ex: `ModelViewProjectionMatrix`).
+ */
+
+#pragma once
+
+struct GPUShader;
+
+enum eGPUBuiltinShader {
+  /** Glyph drawing shader used by the BLF module. */
+  GPU_SHADER_TEXT,
+  /** Draws keyframe markers. All markers shapes are supported through a single shader. */
+  GPU_SHADER_KEYFRAME_SHAPE,
+  /** Draw solid mesh with a single distant light using a clamped simple dot product. */
+  GPU_SHADER_SIMPLE_LIGHTING,
+  /** Draw an icon, leaving a semi-transparent rectangle on top of the icon. */
+  GPU_SHADER_ICON,
+  /** Draw a texture with a uniform color multiplied. */
+  GPU_SHADER_2D_IMAGE_RECT_COLOR,
+  /** Draw a texture with a desaturation factor. */
+  GPU_SHADER_2D_IMAGE_DESATURATE_COLOR,
+  /** Draw a group of texture rectangle with an associated color multiplied. */
+  GPU_SHADER_ICON_MULTI,
+  /** Draw a two color checker based on screen position (not UV coordinates). */
+  GPU_SHADER_2D_CHECKER,
+  /** Draw diagonal stripes with two alternating colors. */
+  GPU_SHADER_2D_DIAG_STRIPES,
+  /** Draw dashed lines with custom dash length and uniform color. */
+  GPU_SHADER_3D_LINE_DASHED_UNIFORM_COLOR,
+  /** Draw triangles / lines / points with only depth output. */
+  GPU_SHADER_3D_DEPTH_ONLY,
+  /** Merge viewport overlay texture with the render output. */
+  GPU_SHADER_2D_IMAGE_OVERLAYS_MERGE,
+  GPU_SHADER_2D_IMAGE_OVERLAYS_STEREO_MERGE,
+  /** Merge viewport overlay texture with the render output. */
+  GPU_SHADER_2D_IMAGE_SHUFFLE_COLOR,
+  /** Used for drawing of annotations (former grease pencil). */
+  GPU_SHADER_GPENCIL_STROKE,
+  /** Draw rounded area borders with silky smooth anti-aliasing without any over-draw. */
+  GPU_SHADER_2D_AREA_BORDERS,
+  /** Multi usage widget shaders for drawing buttons and other UI elements. */
+  GPU_SHADER_2D_WIDGET_BASE,
+  GPU_SHADER_2D_WIDGET_BASE_INST,
+  GPU_SHADER_2D_WIDGET_SHADOW,
+  /** Draw a node link given an input quadratic Bezier curve. */
+  GPU_SHADER_2D_NODELINK,
+  GPU_SHADER_2D_NODELINK_INST,
+
+  /** Draw round points with per vertex size and color. */
+  GPU_SHADER_3D_POINT_VARYING_SIZE_VARYING_COLOR,
+  /** Draw round points with a uniform size. Disabling blending will disable AA. */
+  GPU_SHADER_2D_POINT_UNIFORM_SIZE_UNIFORM_COLOR_AA,
+  GPU_SHADER_3D_POINT_UNIFORM_SIZE_UNIFORM_COLOR_AA,
+  /** Draw round points with a uniform size and an outline. Disabling blending will disable AA. */
+  GPU_SHADER_2D_POINT_UNIFORM_SIZE_UNIFORM_COLOR_OUTLINE_AA,
+
+  /** Draw geometry with uniform color. Has an additional clip plane parameter. */
+  GPU_SHADER_3D_CLIPPED_UNIFORM_COLOR,
+  /** Draw wide lines with uniform color. Has an additional clip plane parameter. */
+  GPU_SHADER_3D_POLYLINE_CLIPPED_UNIFORM_COLOR,
+
+  /** Compute shaders to generate 2d index buffers (mainly for curve drawing). */
+  GPU_SHADER_INDEXBUF_POINTS,
+  GPU_SHADER_INDEXBUF_LINES,
+  GPU_SHADER_INDEXBUF_TRIS,
+
+  /**
+   * ----------------------- Shaders exposed through pyGPU module -----------------------
+   *
+   * Avoid breaking the interface of these shaders as they are used by addons.
+   * Polyline versions are used for drawing wide lines (> 1px width).
+   */
+
+  /**
+   * Take a 3D position and color for each vertex without color interpolation.
+   *
+   * \param color: in vec4
+   * \param pos: in vec3
+   */
+  GPU_SHADER_3D_FLAT_COLOR,
+  GPU_SHADER_3D_POLYLINE_FLAT_COLOR,
+  /**
+   * Take a 3D position and color for each vertex with perspective correct interpolation.
+   *
+   * \param color: in vec4
+   * \param pos: in vec3
+   */
+  GPU_SHADER_3D_SMOOTH_COLOR,
+  GPU_SHADER_3D_POLYLINE_SMOOTH_COLOR,
+  /**
+   * Take a single color for all the vertices and a 3D position for each vertex.
+   *
+   * \param color: uniform vec4
+   * \param pos: in vec3
+   */
+  GPU_SHADER_3D_UNIFORM_COLOR,
+  GPU_SHADER_3D_POLYLINE_UNIFORM_COLOR,
+  /**
+   * Draw a texture in 3D. Take a 3D position and a 2D texture coordinate for each vertex.
+   *
+   * \param image: uniform sampler2D
+   * \param texCoord: in vec2
+   * \param pos: in vec3
+   */
+  GPU_SHADER_3D_IMAGE,
+  /**
+   * Take a 3D position and color for each vertex with linear interpolation in window space.
+   *
+   * \param color: uniform vec4
+   * \param image: uniform sampler2D
+   * \param texCoord: in vec2
+   * \param pos: in vec3
+   */
+  GPU_SHADER_3D_IMAGE_COLOR,
+};
+#define GPU_SHADER_BUILTIN_LEN (GPU_SHADER_3D_IMAGE_COLOR + 1)
+
+/** Support multiple configurations. */
+enum eGPUShaderConfig {
+  GPU_SHADER_CFG_DEFAULT = 0,
+  GPU_SHADER_CFG_CLIPPED = 1,
+};
+#define GPU_SHADER_CFG_LEN (GPU_SHADER_CFG_CLIPPED + 1)
+
+GPUShader *GPU_shader_get_builtin_shader_with_config(eGPUBuiltinShader shader,
+                                                     eGPUShaderConfig sh_cfg);
+GPUShader *GPU_shader_get_builtin_shader(eGPUBuiltinShader shader);
+
+void GPU_shader_free_builtin_shaders();