/****************************************************************************** * Spine Runtimes License Agreement * Last updated April 5, 2025. Replaces all prior versions. * * Copyright (c) 2013-2025, Esoteric Software LLC * * Integration of the Spine Runtimes into software or otherwise creating * derivative works of the Spine Runtimes is permitted under the terms and * conditions of Section 2 of the Spine Editor License Agreement: * http://esotericsoftware.com/spine-editor-license * * Otherwise, it is permitted to integrate the Spine Runtimes into software * or otherwise create derivative works of the Spine Runtimes (collectively, * "Products"), provided that each user of the Products must obtain their own * Spine Editor license and redistribution of the Products in any form must * include this license and copyright notice. * * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *****************************************************************************/ #include "spine-sdl-c.h" #include #define STB_IMAGE_IMPLEMENTATION #include static spine_skeleton_renderer renderer = NULL; static void ensure_renderer(void) { if (!renderer) { renderer = spine_skeleton_renderer_create(); } } void spine_sdl_draw(spine_skeleton_drawable drawable, struct SDL_Renderer *sdl_renderer, bool premultipliedAlpha) { spine_skeleton skeleton = spine_skeleton_drawable_get_skeleton(drawable); spine_sdl_draw_skeleton(skeleton, sdl_renderer, premultipliedAlpha); } void spine_sdl_draw_skeleton(spine_skeleton skeleton, struct SDL_Renderer *sdl_renderer, bool premultipliedAlpha) { ensure_renderer(); spine_render_command command = spine_skeleton_renderer_render(renderer, skeleton); // Pre-allocate vertex and index arrays int max_vertices = 1024; int max_indices = 1024 * 3; SDL_Vertex *vertices = (SDL_Vertex *) malloc(sizeof(SDL_Vertex) * max_vertices); int *indices = (int *) malloc(sizeof(int) * max_indices); while (command) { int num_vertices = spine_render_command_get_num_vertices(command); int num_indices = spine_render_command_get_num_indices(command); // Resize buffers if needed if (num_vertices > max_vertices) { max_vertices = num_vertices * 2; vertices = (SDL_Vertex *) realloc(vertices, sizeof(SDL_Vertex) * max_vertices); } if (num_indices > max_indices) { max_indices = num_indices * 2; indices = (int *) realloc(indices, sizeof(int) * max_indices); } // Get vertex data from render command float *positions = spine_render_command_get_positions(command); float *uvs = spine_render_command_get_uvs(command); uint32_t *colors = spine_render_command_get_colors(command); uint16_t *command_indices = spine_render_command_get_indices(command); SDL_Texture *texture = (SDL_Texture *) spine_render_command_get_texture(command); spine_blend_mode blend_mode = spine_render_command_get_blend_mode(command); // Fill SDL vertices for (int i = 0; i < num_vertices; i++) { vertices[i].position.x = positions[i * 2]; vertices[i].position.y = positions[i * 2 + 1]; vertices[i].tex_coord.x = uvs[i * 2]; vertices[i].tex_coord.y = uvs[i * 2 + 1]; // Convert color from packed uint32 to SDL_Color uint32_t color = colors[i]; vertices[i].color.r = (color >> 24) & 0xFF; vertices[i].color.g = (color >> 16) & 0xFF; vertices[i].color.b = (color >> 8) & 0xFF; vertices[i].color.a = color & 0xFF; } // Copy indices for (int i = 0; i < num_indices; i++) { indices[i] = command_indices[i]; } // Set blend mode if (!premultipliedAlpha) { switch (blend_mode) { case SPINE_BLEND_MODE_NORMAL: SDL_SetTextureBlendMode(texture, SDL_BLENDMODE_BLEND); break; case SPINE_BLEND_MODE_MULTIPLY: SDL_SetTextureBlendMode(texture, SDL_BLENDMODE_MOD); break; case SPINE_BLEND_MODE_ADDITIVE: SDL_SetTextureBlendMode(texture, SDL_BLENDMODE_ADD); break; case SPINE_BLEND_MODE_SCREEN: SDL_SetTextureBlendMode(texture, SDL_BLENDMODE_BLEND); break; } } else { SDL_BlendMode target; switch (blend_mode) { case SPINE_BLEND_MODE_NORMAL: target = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_ONE, SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA, SDL_BLENDOPERATION_ADD, SDL_BLENDFACTOR_ONE, SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA, SDL_BLENDOPERATION_ADD); SDL_SetTextureBlendMode(texture, target); break; case SPINE_BLEND_MODE_MULTIPLY: SDL_SetTextureBlendMode(texture, SDL_BLENDMODE_MOD); break; case SPINE_BLEND_MODE_ADDITIVE: target = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_ONE, SDL_BLENDFACTOR_ONE, SDL_BLENDOPERATION_ADD, SDL_BLENDFACTOR_ONE, SDL_BLENDFACTOR_ONE, SDL_BLENDOPERATION_ADD); SDL_SetTextureBlendMode(texture, target); break; case SPINE_BLEND_MODE_SCREEN: target = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_ONE, SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA, SDL_BLENDOPERATION_ADD, SDL_BLENDFACTOR_ONE, SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA, SDL_BLENDOPERATION_ADD); SDL_SetTextureBlendMode(texture, target); break; } } // Draw the geometry SDL_RenderGeometry(sdl_renderer, texture, vertices, num_vertices, indices, num_indices); // Move to next command spine_render_command next = spine_render_command_get_next(command); command = next; } free(vertices); free(indices); } // Texture loading functions for atlas void *load_texture(const char *path, SDL_Renderer *renderer) { int width, height, components; stbi_uc *imageData = stbi_load(path, &width, &height, &components, 4); if (!imageData) return NULL; SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ABGR8888, SDL_TEXTUREACCESS_STATIC, width, height); if (!texture) { stbi_image_free(imageData); return NULL; } if (SDL_UpdateTexture(texture, NULL, imageData, width * 4)) { SDL_DestroyTexture(texture); stbi_image_free(imageData); return NULL; } stbi_image_free(imageData); return texture; } void unload_texture(void *texture) { SDL_DestroyTexture((SDL_Texture *) texture); }