generate api docs python

1 files changed, 284 insertions, 0 deletions

diff --git a/src/ral/backends/opengl/backend_opengl.c b/src/ral/backends/opengl/backend_opengl.c
new file mode 100644
index 0000000..2c7c411
--- /dev/null
+++ b/src/ral/backends/opengl/backend_opengl.c
@@ -0,0 +1,284 @@
+#include <assert.h>
+#include "backend_opengl.h"
+#include "log.h"
+#include "mem.h"
+#include "ral_common.h"
+#include "ral_impl.h"
+#include "ral_types.h"
+
+#include <glad/glad.h>
+#include <glfw3.h>
+
+typedef struct OpenglCtx {
+    GLFWwindow* window;
+    arena pool_arena;
+    GPU_CmdBuffer main_cmd_buffer;
+    GPU_BackendPools gpu_pools;
+    ResourcePools* resource_pools;
+} OpenglCtx;
+
+static OpenglCtx context;
+
+bool GPU_Backend_Init(const char* window_name, struct GLFWwindow *window, struct ResourcePools* res_pools) {
+    INFO("loading OpenGL backend");
+
+    memset(&context, 0, sizeof(context));
+    context.window = window;
+
+    size_t pool_buffer_size = 1024 * 1024;
+    context.pool_arena = arena_create(malloc(pool_buffer_size), pool_buffer_size);
+
+    BackendPools_Init(&context.pool_arena, &context.gpu_pools);
+    context.resource_pools = res_pools;
+
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);
+    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
+    glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
+
+    // glad: load all opengl function pointers
+    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
+      ERROR("Failed to initialise GLAD \n");
+      return false;
+    }
+
+    glEnable(GL_DEPTH_TEST);
+    glEnable(GL_CULL_FACE);
+
+    return true;
+}
+
+// All of these are no-ops in OpenGL
+void GPU_Backend_Shutdown() {}
+bool GPU_Device_Create(GPU_Device* out_device) { return true; }
+void GPU_Device_Destroy(GPU_Device* device) {}
+bool GPU_Swapchain_Create(GPU_Swapchain* out_swapchain) { return true; }
+void GPU_Swapchain_Destroy(GPU_Swapchain* swapchain) {}
+void GPU_CmdEncoder_Destroy(GPU_CmdEncoder* encoder) {}
+void GPU_CmdEncoder_BeginRender(GPU_CmdEncoder* encoder, GPU_Renderpass* renderpass) {}
+void GPU_CmdEncoder_EndRender(GPU_CmdEncoder* encoder) {}
+GPU_CmdEncoder* GPU_GetDefaultEncoder() {
+    return context.
+}
+void GPU_QueueSubmit(GPU_CmdBuffer* cmd_buffer) {}
+
+GPU_Renderpass* GPU_Renderpass_Create(GPU_RenderpassDesc description) {
+    // allocate new pass
+    GPU_Renderpass* renderpass = Renderpass_pool_alloc(&context.gpu_pools.renderpasses, NULL);
+    renderpass->description = description;
+
+    if (!description.default_framebuffer) {
+        // If we're not using the default framebuffer we need to generate a new one
+        GLuint gl_fbo_id;
+        glGenFramebuffers(1, &gl_fbo_id);
+        renderpass->fbo = gl_fbo_id;
+    } else {
+        renderpass->fbo = OPENGL_DEFAULT_FRAMEBUFFER;
+        assert(!description.has_color_target);
+        assert(!description.has_depth_stencil);
+    }
+    glBindFramebuffer(GL_FRAMEBUFFER, renderpass->fbo);
+
+    if (description.has_color_target && !description.default_framebuffer) {
+      GPU_Texture* colour_attachment = TEXTURE_GET(description.color_target);
+      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
+                             colour_attachment->id, 0);
+    }
+    if (description.has_depth_stencil && !description.default_framebuffer) {
+      GPU_Texture* depth_attachment = TEXTURE_GET(description.depth_stencil);
+      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth_attachment->id,
+                             0);
+    }
+
+    if (description.has_depth_stencil && !description.has_color_target) {
+      glDrawBuffer(GL_NONE);
+      glReadBuffer(GL_NONE);
+    }
+
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);  // reset to default framebuffer
+
+    return renderpass;
+}
+
+void GPU_Renderpass_Destroy(GPU_Renderpass* pass) { glDeleteFramebuffers(1, &pass->fbo); }
+
+GPU_Pipeline* GPU_GraphicsPipeline_Create(GraphicsPipelineDesc description, GPU_Renderpass* renderpass) {
+    GPU_Pipeline* pipeline = Pipeline_pool_alloc(&context.gpu_pools.pipelines, NULL);
+
+    // Create shader program
+    u32 shader_id = shader_create_separate(description.vs.filepath.buf, description.fs.filepath.buf);
+    pipeline->shader_id = shader_id;
+
+    // Vertex format
+    pipeline->vertex_desc = description.vertex_desc;
+
+    // Allocate uniform buffers if needed
+    u32 ubo_count = 0;
+    // printf("data layouts %d\n", description.data_layouts_count);
+    for (u32 layout_i = 0; layout_i < description.data_layouts_count; layout_i++) {
+      ShaderDataLayout sdl = description.data_layouts[layout_i].get_layout(NULL);
+      TRACE("Got shader data layout %d's bindings! . found %d", layout_i, sdl.binding_count);
+
+      for (u32 binding_j = 0; binding_j < sdl.binding_count; binding_j++) {
+        u32 binding_id = binding_j;
+        assert(binding_id < MAX_PIPELINE_UNIFORM_BUFFERS);
+        ShaderBinding binding = sdl.bindings[binding_j];
+        // Do I want Buffer vs Bytes?
+        if (binding.kind == BINDING_BUFFER) {
+          static u32 s_binding_point = 0;
+          BufferHandle ubo_handle =
+              GPU_BufferCreate(binding.data.bytes.size, BUFFER_UNIFORM, BUFFER_FLAG_GPU, NULL);  // no data right now
+          pipeline->uniform_bindings[ubo_count++] = ubo_handle;
+          GPU_Buffer* ubo_buf = BUFFER_GET(ubo_handle);
+
+          i32 blockIndex = glGetUniformBlockIndex(pipeline->shader_id, binding.label);
+          printf("Block index for %s: %d", binding.label, blockIndex);
+          if (blockIndex < 0) {
+            WARN("Couldn't retrieve block index for uniform block '%s'", binding.label);
+          } else {
+            // DEBUG("Retrived block index %d for %s", blockIndex, binding.label);
+          }
+          u32 blocksize;
+          glGetActiveUniformBlockiv(pipeline->shader_id, blockIndex, GL_UNIFORM_BLOCK_DATA_SIZE,
+                                    &blocksize);
+          printf("\t with size %d bytes\n", blocksize);
+
+          glBindBufferBase(GL_UNIFORM_BUFFER, s_binding_point, ubo_buf->id.ubo);
+          if (blockIndex != GL_INVALID_INDEX) {
+            glUniformBlockBinding(pipeline->shader_id, blockIndex, s_binding_point);
+          }
+          ubo_buf->ubo_binding_point = s_binding_point++;
+          ubo_buf->name = binding.label;
+          assert(s_binding_point < GL_MAX_UNIFORM_BUFFER_BINDINGS);
+        }
+      }
+    }
+    pipeline->uniform_count = ubo_count;
+
+    pipeline->renderpass = description.renderpass;
+    pipeline->wireframe = description.wireframe;
+
+    return pipeline;
+}
+
+void GraphicsPipeline_Destroy(GPU_Pipeline* pipeline) {}
+
+GPU_CmdEncoder GPU_CmdEncoder_Create() {
+  GPU_CmdEncoder encoder = { 0 };
+  return encoder;
+}
+
+
+BufferHandle GPU_BufferCreate(u64 size, GPU_BufferType buf_type, GPU_BufferFlags flags, const void *data) {
+    // "allocating" the cpu-side buffer struct
+    BufferHandle handle;
+    GPU_Buffer* buffer = Buffer_pool_alloc(&context.resource_pools, &handle);
+    buffer->size = size;
+    buffer->vao = 0;
+
+    // Opengl buffer
+    GLuint gl_buffer_id;
+    glGenBuffers(1, &gl_buffer_id);
+
+    GLenum gl_buf_type;
+    GLenum gl_buf_usage = GL_STATIC_DRAW;
+
+    switch (buf_type) {
+      case BUFFER_UNIFORM:
+        DEBUG("Creating Uniform buffer");
+        gl_buf_type = GL_UNIFORM_BUFFER;
+        /* gl_buf_usage = GL_DYNAMIC_DRAW; */
+        buffer->id.ubo = gl_buffer_id;
+        break;
+      case BUFFER_DEFAULT:
+      case BUFFER_VERTEX:
+        DEBUG("Creating Vertex buffer");
+        gl_buf_type = GL_ARRAY_BUFFER;
+        buffer->id.vbo = gl_buffer_id;
+        break;
+      case BUFFER_INDEX:
+        DEBUG("Creating Index buffer");
+        gl_buf_type = GL_ELEMENT_ARRAY_BUFFER;
+        buffer->id.ibo = gl_buffer_id;
+        break;
+      default:
+        WARN("Unimplemented gpu_buffer_type provided %s", buffer_type_names[buf_type]);
+        break;
+    }
+    // bind buffer
+    glBindBuffer(gl_buf_type, gl_buffer_id);
+
+    if (data) {
+      TRACE("Upload data (%d bytes) as part of buffer creation", size);
+      glBufferData(gl_buf_type, buffer->size, data, gl_buf_usage);
+    } else {
+      TRACE("Allocating but not uploading (%d bytes)", size);
+      glBufferData(gl_buf_type, buffer->size, NULL, gl_buf_usage);
+    }
+
+    glBindBuffer(gl_buf_type, 0);
+
+    return handle;
+}
+
+TextureHandle GPU_TextureCreate(TextureDesc desc, bool create_view, const void *data) {
+    // "allocating" the cpu-side struct
+    TextureHandle handle;
+    GPU_Texture* texture = Texture_pool_alloc(&context.resource_pools->textures, &handle);
+    DEBUG("Allocated texture with handle %d", handle.raw);
+
+    GLuint gl_texture_id;
+    glGenTextures(1, &gl_texture_id);
+    texture->id = gl_texture_id;
+
+    glBindTexture(GL_TEXTURE_2D, gl_texture_id);
+
+    GLint internal_format =
+        desc.format == TEXTURE_FORMAT_DEPTH_DEFAULT ? GL_DEPTH_COMPONENT : GL_RGB;
+    GLenum format = desc.format == TEXTURE_FORMAT_DEPTH_DEFAULT ? GL_DEPTH_COMPONENT : GL_RGBA;
+    GLenum data_type = desc.format == TEXTURE_FORMAT_DEPTH_DEFAULT ? GL_FLOAT : GL_UNSIGNED_BYTE;
+
+    if (desc.format == TEXTURE_FORMAT_DEPTH_DEFAULT) {
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+    } else {
+      // set the texture wrapping parameters
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
+                      GL_REPEAT);  // set texture wrapping to GL_REPEAT (default wrapping method)
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+      // set texture filtering parameters
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    }
+
+    if (data) {
+      glTexImage2D(GL_TEXTURE_2D, 0, internal_format, desc.extents.x, desc.extents.y, 0, format,
+                   data_type, data);
+      glGenerateMipmap(GL_TEXTURE_2D);
+    } else {
+      WARN("No image data provided");
+      glTexImage2D(GL_TEXTURE_2D, 0, internal_format, desc.extents.x, desc.extents.y, 0, format,
+                   data_type, NULL);
+    }
+
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    return handle;
+}
+
+void GPU_TextureDestroy(TextureHandle handle) {
+    glDeleteTextures(1, &handle.raw);
+}
+
+// TODO: void GPU_TextureUpload(TextureHandle handle, size_t n_bytes, const void* data)
+
+bool GPU_Backend_BeginFrame() {
+    glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+}
+
+void GPU_Backend_EndFrame() {
+    glfwSwapBuffers(context.window);
+}