1 files changed, 378 insertions, 0 deletions
diff --git a/source/blender/gpu/intern/gpu_uniformbuffer.c b/source/blender/gpu/intern/gpu_uniformbuffer.c
new file mode 100644
index 00000000000..6d52dab5a1f
--- /dev/null
+++ b/source/blender/gpu/intern/gpu_uniformbuffer.c
@@ -0,0 +1,378 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2005 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): Clement Foucault.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file gpu_uniformbuffer.c
+ *  \ingroup gpu
+ */
+
+#include <string.h>
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+
+#include "gpu_codegen.h"
+
+#include "GPU_extensions.h"
+#include "GPU_glew.h"
+#include "GPU_material.h"
+#include "GPU_uniformbuffer.h"
+
+typedef enum GPUUniformBufferFlag {
+	GPU_UBO_FLAG_INITIALIZED = (1 << 0),
+	GPU_UBO_FLAG_DIRTY = (1 << 1),
+} GPUUniformBufferFlag;
+
+typedef enum GPUUniformBufferType {
+	GPU_UBO_STATIC = 0,
+	GPU_UBO_DYNAMIC = 1,
+} GPUUniformBufferType;
+
+struct GPUUniformBuffer {
+	int size;           /* in bytes */
+	GLuint bindcode;    /* opengl identifier for UBO */
+	int bindpoint;      /* current binding point */
+	GPUUniformBufferType type;
+};
+
+#define GPUUniformBufferStatic GPUUniformBuffer
+
+typedef struct GPUUniformBufferDynamic {
+	GPUUniformBuffer buffer;
+	ListBase items;				/* GPUUniformBufferDynamicItem */
+	void *data;
+	char flag;
+} GPUUniformBufferDynamic;
+
+struct GPUUniformBufferDynamicItem {
+	struct GPUUniformBufferDynamicItem *next, *prev;
+	GPUType gputype;
+	float *data;
+	int size;
+};
+
+
+/* Prototypes */
+static GPUType get_padded_gpu_type(struct LinkData *link);
+static void gpu_uniformbuffer_inputs_sort(struct ListBase *inputs);
+
+static GPUUniformBufferDynamicItem *gpu_uniformbuffer_populate(
+        GPUUniformBufferDynamic *ubo, const GPUType gputype, float *num);
+
+/* Only support up to this type, if you want to extend it, make sure the
+ * padding logic is correct for the new types. */
+#define MAX_UBO_GPU_TYPE GPU_VEC4
+
+static void gpu_uniformbuffer_initialize(GPUUniformBuffer *ubo, const void *data)
+{
+	glBindBuffer(GL_UNIFORM_BUFFER, ubo->bindcode);
+	glBufferData(GL_UNIFORM_BUFFER, ubo->size, data, GL_DYNAMIC_DRAW);
+	glBindBuffer(GL_UNIFORM_BUFFER, 0);
+}
+
+GPUUniformBuffer *GPU_uniformbuffer_create(int size, const void *data, char err_out[256])
+{
+	GPUUniformBuffer *ubo = MEM_callocN(sizeof(GPUUniformBufferStatic), "GPUUniformBufferStatic");
+	ubo->size = size;
+	ubo->bindpoint = -1;
+
+	/* Generate Buffer object */
+	glGenBuffers(1, &ubo->bindcode);
+	
+	if (!ubo->bindcode) {
+		if (err_out)
+			BLI_snprintf(err_out, 256, "GPUUniformBuffer: UBO create failed");
+		GPU_uniformbuffer_free(ubo);
+		return NULL;
+	}
+
+	if (ubo->size > GPU_max_ubo_size()) {
+		if (err_out)
+			BLI_snprintf(err_out, 256, "GPUUniformBuffer: UBO too big");
+		GPU_uniformbuffer_free(ubo);
+		return NULL;
+	}
+
+	gpu_uniformbuffer_initialize(ubo, data);
+	return ubo;
+}
+
+/**
+ * Create dynamic UBO from parameters
+ * Return NULL if failed to create or if \param inputs is empty.
+ *
+ * \param inputs ListBase of BLI_genericNodeN(GPUInput)
+ */
+GPUUniformBuffer *GPU_uniformbuffer_dynamic_create(ListBase *inputs, char err_out[256])
+{
+	/* There is no point on creating an UBO if there is no arguments. */
+	if (BLI_listbase_is_empty(inputs)) {
+		return NULL;
+	}
+
+	GPUUniformBufferDynamic *ubo = MEM_callocN(sizeof(GPUUniformBufferDynamic), "GPUUniformBufferDynamic");
+	ubo->buffer.type = GPU_UBO_DYNAMIC;
+	ubo->buffer.bindpoint = -1;
+	ubo->flag = GPU_UBO_FLAG_DIRTY;
+
+	/* Generate Buffer object. */
+	glGenBuffers(1, &ubo->buffer.bindcode);
+
+	if (!ubo->buffer.bindcode) {
+		if (err_out)
+			BLI_snprintf(err_out, 256, "GPUUniformBuffer: UBO create failed");
+		GPU_uniformbuffer_free(&ubo->buffer);
+		return NULL;
+	}
+
+	if (ubo->buffer.size > GPU_max_ubo_size()) {
+		if (err_out)
+			BLI_snprintf(err_out, 256, "GPUUniformBuffer: UBO too big");
+		GPU_uniformbuffer_free(&ubo->buffer);
+		return NULL;
+	}
+
+	/* Make sure we comply to the ubo alignment requirements. */
+	gpu_uniformbuffer_inputs_sort(inputs);
+
+	for (LinkData *link = inputs->first; link; link = link->next) {
+		GPUInput *input = link->data;
+		GPUType gputype = get_padded_gpu_type(link);
+		gpu_uniformbuffer_populate(ubo, gputype, input->dynamicvec);
+	}
+
+	ubo->data = MEM_mallocN(ubo->buffer.size, __func__);
+
+	/* Initialize buffer data. */
+	GPU_uniformbuffer_dynamic_update(&ubo->buffer);
+	return &ubo->buffer;
+}
+
+/**
+ * Free the data, and clean the items list.
+ */
+static void gpu_uniformbuffer_dynamic_reset(GPUUniformBufferDynamic *ubo)
+{
+	ubo->buffer.size = 0;
+	if (ubo->data) {
+		MEM_freeN(ubo->data);
+	}
+	BLI_freelistN(&ubo->items);
+}
+
+void GPU_uniformbuffer_free(GPUUniformBuffer *ubo)
+{
+	if (ubo->type == GPU_UBO_DYNAMIC) {
+		gpu_uniformbuffer_dynamic_reset((GPUUniformBufferDynamic *)ubo);
+	}
+
+	glDeleteBuffers(1, &ubo->bindcode);
+	MEM_freeN(ubo);
+}
+
+static void gpu_uniformbuffer_update(GPUUniformBuffer *ubo, const void *data)
+{
+	glBindBuffer(GL_UNIFORM_BUFFER, ubo->bindcode);
+	glBufferSubData(GL_UNIFORM_BUFFER, 0, ubo->size, data);
+	glBindBuffer(GL_UNIFORM_BUFFER, 0);
+}
+
+void GPU_uniformbuffer_update(GPUUniformBuffer *ubo, const void *data)
+{
+	BLI_assert(ubo->type == GPU_UBO_STATIC);
+	gpu_uniformbuffer_update(ubo, data);
+}
+
+/**
+ * We need to recalculate the internal data, and re-generate it
+ * from its populated items.
+ */
+void GPU_uniformbuffer_dynamic_update(GPUUniformBuffer *ubo_)
+{
+	BLI_assert(ubo_->type == GPU_UBO_DYNAMIC);
+	GPUUniformBufferDynamic *ubo = (GPUUniformBufferDynamic *)ubo_;
+
+	float *offset = ubo->data;
+	for (GPUUniformBufferDynamicItem *item = ubo->items.first; item; item = item->next) {
+		memcpy(offset, item->data, item->size);
+		offset += item->gputype;
+	}
+
+	if (ubo->flag & GPU_UBO_FLAG_INITIALIZED) {
+		gpu_uniformbuffer_update(ubo_, ubo->data);
+	}
+	else {
+		ubo->flag |= GPU_UBO_FLAG_INITIALIZED;
+		gpu_uniformbuffer_initialize(ubo_, ubo->data);
+	}
+
+	ubo->flag &= ~GPU_UBO_FLAG_DIRTY;
+}
+
+/**
+ * We need to pad some data types (vec3) on the C side
+ * To match the GPU expected memory block alignment.
+ */
+static GPUType get_padded_gpu_type(LinkData *link)
+{
+	GPUInput *input = link->data;
+	GPUType gputype = input->type;
+
+	/* Unless the vec3 is followed by a float we need to treat it as a vec4. */
+	if (gputype == GPU_VEC3 &&
+	    (link->next != NULL) &&
+	    (((GPUInput *)link->next->data)->type != GPU_FLOAT))
+	{
+		gputype = GPU_VEC4;
+	}
+
+	return gputype;
+}
+
+/**
+ * Returns 1 if the first item shold be after second item.
+ * We make sure the vec4 uniforms come first.
+ */
+static int inputs_cmp(const void *a, const void *b)
+{
+	const LinkData *link_a = a, *link_b = b;
+	const GPUInput *input_a = link_a->data, *input_b = link_b->data;
+	return input_a->type < input_b->type ? 1 : 0;
+}
+
+/**
+ * Make sure we respect the expected alignment of UBOs.
+ * vec4, pad vec3 as vec4, then vec2, then floats.
+ */
+static void gpu_uniformbuffer_inputs_sort(ListBase *inputs)
+{
+	/* Order them as vec4, vec3, vec2, float. */
+	BLI_listbase_sort(inputs, inputs_cmp);
+
+	/* Creates a lookup table for the different types; */
+	LinkData *inputs_lookup[MAX_UBO_GPU_TYPE + 1] = {NULL};
+	GPUType cur_type = MAX_UBO_GPU_TYPE + 1;
+
+	for (LinkData *link = inputs->first; link; link = link->next) {
+		GPUInput *input = link->data;
+		if (input->type == cur_type) {
+			continue;
+		}
+		else {
+			inputs_lookup[input->type] = link;
+			cur_type = input->type;
+		}
+	}
+
+	/* If there is no GPU_VEC3 there is no need for alignment. */
+	if (inputs_lookup[GPU_VEC3] == NULL) {
+		return;
+	}
+
+	LinkData *link = inputs_lookup[GPU_VEC3];
+	while (link != NULL && ((GPUInput *)link->data)->type == GPU_VEC3) {
+		LinkData *link_next = link->next;
+
+		/* If GPU_VEC3 is followed by nothing or a GPU_FLOAT, no need for aligment. */
+		if ((link_next == NULL) ||
+		    ((GPUInput *)link_next->data)->type == GPU_FLOAT)
+		{
+			break;
+		}
+
+		/* If there is a float, move it next to current vec3. */
+		if (inputs_lookup[GPU_FLOAT] != NULL) {
+			LinkData *float_input = inputs_lookup[GPU_FLOAT];
+			inputs_lookup[GPU_FLOAT] = float_input->next;
+
+			BLI_remlink(inputs, float_input);
+			BLI_insertlinkafter(inputs, link, float_input);
+		}
+
+		link = link_next;
+	}
+}
+
+/**
+ * This may now happen from the main thread, so we can't update the UBO
+ * We simply flag it as dirty
+ */
+static GPUUniformBufferDynamicItem *gpu_uniformbuffer_populate(
+        GPUUniformBufferDynamic *ubo, const GPUType gputype, float *num)
+{
+	BLI_assert(gputype <= MAX_UBO_GPU_TYPE);
+	GPUUniformBufferDynamicItem *item = MEM_callocN(sizeof(GPUUniformBufferDynamicItem), __func__);
+
+	item->gputype = gputype;
+	item->data = num;
+	item->size = gputype * sizeof(float);
+	ubo->buffer.size += item->size;
+
+	ubo->flag |= GPU_UBO_FLAG_DIRTY;
+	BLI_addtail(&ubo->items, item);
+
+	return item;
+}
+
+void GPU_uniformbuffer_bind(GPUUniformBuffer *ubo, int number)
+{
+	if (number >= GPU_max_ubo_binds()) {
+		fprintf(stderr, "Not enough UBO slots.\n");
+		return;
+	}
+
+	if (ubo->type == GPU_UBO_DYNAMIC) {
+		GPUUniformBufferDynamic *ubo_dynamic = (GPUUniformBufferDynamic *)ubo;
+		if (ubo_dynamic->flag & GPU_UBO_FLAG_DIRTY) {
+			GPU_uniformbuffer_dynamic_update(ubo);
+		}
+	}
+
+	if (ubo->bindcode != 0) {
+		glBindBufferBase(GL_UNIFORM_BUFFER, number, ubo->bindcode);
+	}
+
+	ubo->bindpoint = number;
+}
+
+void GPU_uniformbuffer_unbind(GPUUniformBuffer *ubo)
+{
+	ubo->bindpoint = -1;
+}
+
+int GPU_uniformbuffer_bindpoint(GPUUniformBuffer *ubo)
+{
+	return ubo->bindpoint;
+}
+
+void GPU_uniformbuffer_tag_dirty(GPUUniformBuffer *ubo_)
+{
+	BLI_assert(ubo_->type == GPU_UBO_DYNAMIC);
+	GPUUniformBufferDynamic *ubo = (GPUUniformBufferDynamic *)ubo_;
+	ubo->flag |= GPU_UBO_FLAG_DIRTY;
+}
+
+#undef MAX_UBO_GPU_TYPE