]> git.sesse.net Git - nageru/blobdiff - flow.cpp
Check uniform locations ahead-of-time, for slightly reduced GL overhead.
[nageru] / flow.cpp
index 7096c9e4f478ccccdc724d4273812f3442c64da2..374e07d73ffe40f461f4df605dc159fa19a98a2b 100644 (file)
--- a/flow.cpp
+++ b/flow.cpp
@@ -16,6 +16,8 @@
 #include <assert.h>
 #include <stdio.h>
 
+#include "util.h"
+
 #include <algorithm>
 #include <memory>
 
@@ -25,8 +27,8 @@ using namespace std;
 
 // Operating point 3 (10 Hz on CPU, excluding preprocessing).
 constexpr float patch_overlap_ratio = 0.75f;
-constexpr unsigned coarsest_level = 0;
-constexpr unsigned finest_level = 0;
+constexpr unsigned coarsest_level = 5;
+constexpr unsigned finest_level = 1;
 constexpr unsigned patch_size_pixels = 12;
 
 // Some global OpenGL objects.
@@ -191,9 +193,8 @@ GLuint fill_vertex_attribute(GLuint vao, GLuint glsl_program_num, const string &
        return vbo;
 }
 
-void bind_sampler(GLuint program, const char *uniform_name, GLuint texture_unit, GLuint tex, GLuint sampler)
+void bind_sampler(GLuint program, GLint location, GLuint texture_unit, GLuint tex, GLuint sampler)
 {
-       GLint location = glGetUniformLocation(program, uniform_name);
        if (location == -1) {
                return;
        }
@@ -221,6 +222,8 @@ private:
        GLuint sobel_fs_obj;
        GLuint sobel_program;
        GLuint sobel_vao;
+
+       GLuint uniform_tex, uniform_image_size, uniform_inv_image_size;
 };
 
 Sobel::Sobel()
@@ -240,6 +243,10 @@ Sobel::Sobel()
        GLint texcoord_attrib = glGetAttribLocation(sobel_program, "texcoord");
        glEnableVertexArrayAttrib(sobel_vao, texcoord_attrib);
        glVertexAttribPointer(texcoord_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
+
+       uniform_tex = glGetUniformLocation(sobel_program, "tex");
+       uniform_image_size = glGetUniformLocation(sobel_program, "image_size");
+       uniform_inv_image_size = glGetUniformLocation(sobel_program, "inv_image_size");
 }
 
 void Sobel::exec(GLint tex0_view, GLint grad0_tex, int level_width, int level_height)
@@ -247,9 +254,9 @@ void Sobel::exec(GLint tex0_view, GLint grad0_tex, int level_width, int level_he
        glUseProgram(sobel_program);
        glBindTextureUnit(0, tex0_view);
        glBindSampler(0, nearest_sampler);
-       glProgramUniform1i(sobel_program, glGetUniformLocation(sobel_program, "tex"), 0);
-       glProgramUniform1f(sobel_program, glGetUniformLocation(sobel_program, "inv_width"), 1.0f / level_width);
-       glProgramUniform1f(sobel_program, glGetUniformLocation(sobel_program, "inv_height"), 1.0f / level_height);
+       glProgramUniform1i(sobel_program, uniform_tex, 0);
+       glProgramUniform2f(sobel_program, uniform_image_size, level_width, level_height);
+       glProgramUniform2f(sobel_program, uniform_inv_image_size, 1.0f / level_width, 1.0f / level_height);
 
        GLuint grad0_fbo;  // TODO: cleanup
        glCreateFramebuffers(1, &grad0_fbo);
@@ -274,6 +281,9 @@ private:
        GLuint motion_fs_obj;
        GLuint motion_search_program;
        GLuint motion_search_vao;
+
+       GLuint uniform_image_size, uniform_inv_image_size;
+       GLuint uniform_image0_tex, uniform_image1_tex, uniform_grad0_tex, uniform_flow_tex;
 };
 
 MotionSearch::MotionSearch()
@@ -294,21 +304,26 @@ MotionSearch::MotionSearch()
        GLint texcoord_attrib = glGetAttribLocation(motion_search_program, "texcoord");
        glEnableVertexArrayAttrib(motion_search_vao, texcoord_attrib);
        glVertexAttribPointer(texcoord_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
+
+       uniform_image_size = glGetUniformLocation(motion_search_program, "image_size");
+       uniform_inv_image_size = glGetUniformLocation(motion_search_program, "inv_image_size");
+       uniform_image0_tex = glGetUniformLocation(motion_search_program, "image0_tex");
+       uniform_image1_tex = glGetUniformLocation(motion_search_program, "image1_tex");
+       uniform_grad0_tex = glGetUniformLocation(motion_search_program, "grad0_tex");
+       uniform_flow_tex = glGetUniformLocation(motion_search_program, "flow_tex");
 }
 
 void MotionSearch::exec(GLuint tex0_view, GLuint tex1_view, GLuint grad0_tex, GLuint flow_tex, GLuint flow_out_tex, int level_width, int level_height, int width_patches, int height_patches)
 {
        glUseProgram(motion_search_program);
 
-       bind_sampler(motion_search_program, "image0_tex", 0, tex0_view, nearest_sampler);
-       bind_sampler(motion_search_program, "image1_tex", 1, tex1_view, linear_sampler);
-       bind_sampler(motion_search_program, "grad0_tex", 2, grad0_tex, nearest_sampler);
-       bind_sampler(motion_search_program, "flow_tex", 3, flow_tex, nearest_sampler);
+       bind_sampler(motion_search_program, uniform_image0_tex, 0, tex0_view, nearest_sampler);
+       bind_sampler(motion_search_program, uniform_image1_tex, 1, tex1_view, linear_sampler);
+       bind_sampler(motion_search_program, uniform_grad0_tex, 2, grad0_tex, nearest_sampler);
+       bind_sampler(motion_search_program, uniform_flow_tex, 3, flow_tex, linear_sampler);
 
-       glProgramUniform1f(motion_search_program, glGetUniformLocation(motion_search_program, "image_width"), level_width);
-       glProgramUniform1f(motion_search_program, glGetUniformLocation(motion_search_program, "image_height"), level_height);
-       glProgramUniform1f(motion_search_program, glGetUniformLocation(motion_search_program, "inv_image_width"), 1.0f / level_width);
-       glProgramUniform1f(motion_search_program, glGetUniformLocation(motion_search_program, "inv_image_height"), 1.0f / level_height);
+       glProgramUniform2f(motion_search_program, uniform_image_size, level_width, level_height);
+       glProgramUniform2f(motion_search_program, uniform_inv_image_size, 1.0f / level_width, 1.0f / level_height);
 
        GLuint flow_fbo;  // TODO: cleanup
        glCreateFramebuffers(1, &flow_fbo);
@@ -339,6 +354,9 @@ private:
        GLuint densify_fs_obj;
        GLuint densify_program;
        GLuint densify_vao;
+
+       GLuint uniform_width_patches, uniform_patch_size, uniform_patch_spacing;
+       GLuint uniform_image0_tex, uniform_image1_tex, uniform_flow_tex;
 };
 
 Densify::Densify()
@@ -355,24 +373,31 @@ Densify::Densify()
        GLint position_attrib = glGetAttribLocation(densify_program, "position");
        glEnableVertexArrayAttrib(densify_vao, position_attrib);
        glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
+
+       uniform_width_patches = glGetUniformLocation(densify_program, "width_patches");
+       uniform_patch_size = glGetUniformLocation(densify_program, "patch_size");
+       uniform_patch_spacing = glGetUniformLocation(densify_program, "patch_spacing");
+       uniform_image0_tex = glGetUniformLocation(densify_program, "image0_tex");
+       uniform_image1_tex = glGetUniformLocation(densify_program, "image1_tex");
+       uniform_flow_tex = glGetUniformLocation(densify_program, "flow_tex");
 }
 
 void Densify::exec(GLuint tex0_view, GLuint tex1_view, GLuint flow_tex, GLuint dense_flow_tex, int level_width, int level_height, int width_patches, int height_patches)
 {
        glUseProgram(densify_program);
 
-       bind_sampler(densify_program, "image0_tex", 0, tex0_view, nearest_sampler);
-       bind_sampler(densify_program, "image1_tex", 1, tex1_view, linear_sampler);
-       bind_sampler(densify_program, "flow_tex", 2, flow_tex, nearest_sampler);
+       bind_sampler(densify_program, uniform_image0_tex, 0, tex0_view, nearest_sampler);
+       bind_sampler(densify_program, uniform_image1_tex, 1, tex1_view, linear_sampler);
+       bind_sampler(densify_program, uniform_flow_tex, 2, flow_tex, nearest_sampler);
 
-       glProgramUniform1i(densify_program, glGetUniformLocation(densify_program, "width_patches"), width_patches);
-       glProgramUniform2f(densify_program, glGetUniformLocation(densify_program, "patch_size"),
+       glProgramUniform1i(densify_program, uniform_width_patches, width_patches);
+       glProgramUniform2f(densify_program, uniform_patch_size,
                float(patch_size_pixels) / level_width,
                float(patch_size_pixels) / level_height);
 
        float patch_spacing_x = float(level_width - patch_size_pixels) / (width_patches - 1);
        float patch_spacing_y = float(level_height - patch_size_pixels) / (height_patches - 1);
-       glProgramUniform2f(densify_program, glGetUniformLocation(densify_program, "patch_spacing"),
+       glProgramUniform2f(densify_program, uniform_patch_spacing,
                patch_spacing_x / level_width,
                patch_spacing_y / level_height);
 
@@ -444,113 +469,116 @@ int main(void)
        glNamedBufferData(vertex_vbo, sizeof(vertices), vertices, GL_STATIC_DRAW);
        glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
 
-       // Coarsest level.
-       int level = coarsest_level;
-       int level_width = WIDTH >> level;
-       int level_height = HEIGHT >> level;
-       float patch_spacing_pixels = patch_size_pixels * (1.0f - patch_overlap_ratio);
-       int width_patches = 1 + lrintf((level_width - patch_size_pixels) / patch_spacing_pixels);
-       int height_patches = 1 + lrintf((level_height - patch_size_pixels) / patch_spacing_pixels);
-
-       // Make sure we always read from the correct level; the chosen
-       // mipmapping could otherwise be rather unpredictable, especially
-       // during motion search.
-       GLuint tex0_view, tex1_view;
-       glGenTextures(1, &tex0_view);
-       glTextureView(tex0_view, GL_TEXTURE_2D, tex0, GL_R8, level, 1, 0, 1);
-       glGenTextures(1, &tex1_view);
-       glTextureView(tex1_view, GL_TEXTURE_2D, tex1, GL_R8, level, 1, 0, 1);
-
-       Sobel sobel;
+       // Initial flow is zero, 1x1.
+       GLuint initial_flow_tex;
+       glCreateTextures(GL_TEXTURE_2D, 1, &initial_flow_tex);
+       glTextureStorage2D(initial_flow_tex, 1, GL_RGB32F, 1, 1);
 
-       // Create a new texture; we could be fancy and render use a multi-level
-       // texture, but meh.
-       GLuint grad0_tex;
-       glCreateTextures(GL_TEXTURE_2D, 1, &grad0_tex);
-       glTextureStorage2D(grad0_tex, 1, GL_RG16F, level_width, level_height);
+       GLuint prev_level_flow_tex = initial_flow_tex;
 
-       sobel.exec(tex0_view, grad0_tex, level_width, level_height);
-
-       // Motion search to find the initial flow.
+       Sobel sobel;
        MotionSearch motion_search;
-
-       // Create a flow texture, initialized to zero.
-       GLuint flow_tex;
-       glCreateTextures(GL_TEXTURE_2D, 1, &flow_tex);
-       glTextureStorage2D(flow_tex, 1, GL_RG16F, width_patches, height_patches);
-
-       // And an output flow texture. (Well, we could have used texture barriers,
-       // but I don't feel lucky today.)
-       GLuint flow_out_tex;
-       glCreateTextures(GL_TEXTURE_2D, 1, &flow_out_tex);
-       glTextureStorage2D(flow_out_tex, 1, GL_RG16F, width_patches, height_patches);
-
-       // And draw.
-       motion_search.exec(tex0_view, tex1_view, grad0_tex, flow_tex, flow_out_tex, level_width, level_height, width_patches, height_patches);
-
-       // Densification.
        Densify densify;
 
-       // Set up an output texture.
-       GLuint dense_flow_tex;
-       glCreateTextures(GL_TEXTURE_2D, 1, &dense_flow_tex);
-       //glTextureStorage2D(dense_flow_tex, 1, GL_RGB16F, level_width, level_height);
-       glTextureStorage2D(dense_flow_tex, 1, GL_RGBA32F, level_width, level_height);
-
-       // And draw.
-       densify.exec(tex0_view, tex1_view, flow_out_tex, dense_flow_tex, level_width, level_height, width_patches, height_patches);
-
-       // TODO: Variational refinement.
-
+       GLuint query;
+       glGenQueries(1, &query);
+       glBeginQuery(GL_TIME_ELAPSED, query);
+
+       for (int level = coarsest_level; level >= int(finest_level); --level) {
+               int level_width = WIDTH >> level;
+               int level_height = HEIGHT >> level;
+               float patch_spacing_pixels = patch_size_pixels * (1.0f - patch_overlap_ratio);
+               int width_patches = 1 + lrintf((level_width - patch_size_pixels) / patch_spacing_pixels);
+               int height_patches = 1 + lrintf((level_height - patch_size_pixels) / patch_spacing_pixels);
+
+               // Make sure we always read from the correct level; the chosen
+               // mipmapping could otherwise be rather unpredictable, especially
+               // during motion search.
+               // TODO: create these beforehand, and stop leaking them.
+               GLuint tex0_view, tex1_view;
+               glGenTextures(1, &tex0_view);
+               glTextureView(tex0_view, GL_TEXTURE_2D, tex0, GL_R8, level, 1, 0, 1);
+               glGenTextures(1, &tex1_view);
+               glTextureView(tex1_view, GL_TEXTURE_2D, tex1, GL_R8, level, 1, 0, 1);
+
+               // Create a new texture; we could be fancy and render use a multi-level
+               // texture, but meh.
+               GLuint grad0_tex;
+               glCreateTextures(GL_TEXTURE_2D, 1, &grad0_tex);
+               glTextureStorage2D(grad0_tex, 1, GL_RG16F, level_width, level_height);
+
+               // Find the derivative.
+               sobel.exec(tex0_view, grad0_tex, level_width, level_height);
+
+               // Motion search to find the initial flow. We use the flow from the previous
+               // level (sampled bilinearly; no fancy tricks) as a guide, then search from there.
+
+               // Create an output flow texture.
+               GLuint flow_out_tex;
+               glCreateTextures(GL_TEXTURE_2D, 1, &flow_out_tex);
+               glTextureStorage2D(flow_out_tex, 1, GL_RG16F, width_patches, height_patches);
+
+               // And draw.
+               motion_search.exec(tex0_view, tex1_view, grad0_tex, prev_level_flow_tex, flow_out_tex, level_width, level_height, width_patches, height_patches);
+
+               // Densification.
+
+               // Set up an output texture (initially zero).
+               GLuint dense_flow_tex;
+               glCreateTextures(GL_TEXTURE_2D, 1, &dense_flow_tex);
+               //glTextureStorage2D(dense_flow_tex, 1, GL_RGB16F, level_width, level_height);
+               glTextureStorage2D(dense_flow_tex, 1, GL_RGBA32F, level_width, level_height);
+
+               // And draw.
+               densify.exec(tex0_view, tex1_view, flow_out_tex, dense_flow_tex, level_width, level_height, width_patches, height_patches);
+
+               // TODO: Variational refinement.
+
+               prev_level_flow_tex = dense_flow_tex;
+       }
+       glEndQuery(GL_TIME_ELAPSED);
+
+       GLint available;
+       do {
+               glGetQueryObjectiv(query, GL_QUERY_RESULT_AVAILABLE, &available);
+       } while (!available);
+       GLuint64 time_elapsed;
+       glGetQueryObjectui64v(query, GL_QUERY_RESULT, &time_elapsed);
+       fprintf(stderr, "GPU time used = %.1f ms\n", time_elapsed / 1e6);
+
+       int level_width = WIDTH >> finest_level;
+       int level_height = HEIGHT >> finest_level;
        unique_ptr<float[]> dense_flow(new float[level_width * level_height * 3]);
-       glGetTextureImage(dense_flow_tex, 0, GL_RGB, GL_FLOAT, level_width * level_height * 3 * sizeof(float), dense_flow.get());
+       glGetTextureImage(prev_level_flow_tex, 0, GL_RGB, GL_FLOAT, level_width * level_height * 3 * sizeof(float), dense_flow.get());
 
        FILE *fp = fopen("flow.ppm", "wb");
+       FILE *flowfp = fopen("flow.flo", "wb");
        fprintf(fp, "P6\n%d %d\n255\n", level_width, level_height);
-       for (unsigned y = 0; y < level_height; ++y) {
+       fprintf(flowfp, "FEIH");
+       fwrite(&level_width, 4, 1, flowfp);
+       fwrite(&level_height, 4, 1, flowfp);
+       for (unsigned y = 0; y < unsigned(level_height); ++y) {
                int yy = level_height - y - 1;
-               for (unsigned x = 0; x < level_width; ++x) {
+               for (unsigned x = 0; x < unsigned(level_width); ++x) {
                        float du = dense_flow[(yy * level_width + x) * 3 + 0];
                        float dv = dense_flow[(yy * level_width + x) * 3 + 1];
                        float w = dense_flow[(yy * level_width + x) * 3 + 2];
 
-                       du /= w;
-                       dv /= w;
-
-                       float angle = atan2(dv * level_width, du * level_height);
-                       float magnitude = min(hypot(du * level_width, dv * level_height) / 20.0, 1.0);
-                       
-                       // HSV to RGB (from Wikipedia). Saturation is 1.
-                       float c = magnitude;
-                       float h = (angle + M_PI) * 6.0 / (2.0 * M_PI);
-                       float X = c * (1.0 - fabs(fmod(h, 2.0) - 1.0));
-                       float r = 0.0f, g = 0.0f, b = 0.0f;
-                       if (h < 1.0f) {
-                               r = c; g = X;
-                       } else if (h < 2.0f) {
-                               r = X; g = c;
-                       } else if (h < 3.0f) {
-                               g = c; b = X;
-                       } else if (h < 4.0f) {
-                               g = X; b = c;
-                       } else if (h < 5.0f) {
-                               r = X; b = c;
-                       } else if (h < 6.0f) {
-                               r = c; b = X;
-                       } else {
-                               // h is NaN, so black is fine.
-                       }
-                       float m = magnitude - c;
-                       r += m; g += m; b += m;
-                       r = max(min(r, 1.0f), 0.0f);
-                       g = max(min(g, 1.0f), 0.0f);
-                       b = max(min(b, 1.0f), 0.0f);
-                       putc(lrintf(r * 255.0f), fp);
-                       putc(lrintf(g * 255.0f), fp);
-                       putc(lrintf(b * 255.0f), fp);
+                       du = (du / w) * level_width;
+                       dv = (-dv / w) * level_height;
+
+                       fwrite(&du, 4, 1, flowfp);
+                       fwrite(&dv, 4, 1, flowfp);
+
+                       uint8_t r, g, b;
+                       flow2rgb(du, dv, &r, &g, &b);
+                       putc(r, fp);
+                       putc(g, fp);
+                       putc(b, fp);
                }
        }
        fclose(fp);
+       fclose(flowfp);
 
        fprintf(stderr, "err = %d\n", glGetError());
 }