Correct resize, linear iterpolation draft

5 files changed, 127 insertions, 24 deletions

diff --git a/inc/config.h b/inc/config.h
index c336c51..680d893 100644
--- a/inc/config.h
+++ b/inc/config.h
@@ -1,9 +1,20 @@
 #ifndef CONFIG_H
 # define CONFIG_H
 
-# define MANDEL_WINDOW_WIDTH  640
-# define MANDEL_WINDOW_HEIGHT 480
+# include "mandel.h"
+
+# define MANDEL_WINDOW_WIDTH  400
+# define MANDEL_WINDOW_HEIGHT 400
 # define MANDEL_WINDOW_TITLE "Mandelbrot"
 # define MANDEL_ITERATIONS 50
 
+static ControlPoint g_theme[] = {
+	{0.0,    {0x00, 0x0F, 0x64} },
+	{0.16,   {0x20, 0x6B, 0xCB} },
+	{0.42,   {0xED, 0xFF, 0xFF} },
+	{0.6425, {0xFF, 0xAA, 0x00} },
+	{1.0,    {0x00, 0x02, 0x00} },
+	// {0.8575, {0x00, 0x02, 0x00} },
+};
+
 #endif
diff --git a/inc/mandel.h b/inc/mandel.h
index 0383a39..a2af137 100644
--- a/inc/mandel.h
+++ b/inc/mandel.h
@@ -58,6 +58,12 @@ typedef struct
 
 typedef struct
 {
+	float	position;
+	Color	color;
+}			ControlPoint;
+
+typedef struct
+{
 	unsigned int	id;
 	struct
 	{
diff --git a/src/color.c b/src/color.c
index 24ca2f2..40d43d5 100644
--- a/src/color.c
+++ b/src/color.c
@@ -1,19 +1,95 @@
 #include "mandel.h"
+#include "config.h"
 
 #define MAX(x, y) (x > y ? x : y)
 #define MIN(x, y) (x < y ? x : y)
 
 static Color	color_hsl_to_rgb(ColorHSL color_hsl);
+static Color	*st_hsl_rainbow(int count);
+static int		st_compar_control_points(const void *ptr1, const void *ptr2);
+static Color	*st_linear_iterpolation(int count, ControlPoint *points, size_t points_count);
 
 unsigned int	color_texture_new(int count)
 {
-	ColorHSL		hsl;
-	Color			*palette;
 	unsigned int	texture;
+	Color			*palette;
 
-    palette = malloc(sizeof(Color) * count);
-	if (palette == NULL)
+	if ((palette = st_hsl_rainbow(count)) == NULL)
 		return 0;
+	/* if ((palette = st_linear_iterpolation(count, g_theme, sizeof(g_theme) / sizeof(ControlPoint))) == NULL) */
+	/* 	return 0; */
+	GL_CALL(glGenTextures(1, &texture));
+	GL_CALL(glBindTexture(GL_TEXTURE_1D, texture));
+	GL_CALL(glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST));
+	GL_CALL(glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST));
+	GL_CALL(glTexImage1D(GL_TEXTURE_1D, 0, GL_RGB, count + 1, 0, GL_RGB, GL_UNSIGNED_BYTE, palette));
+	free(palette);
+	return texture;
+}
+
+static Color	*st_linear_iterpolation(int count, ControlPoint *points, size_t points_count)
+{
+	Color			*palette;
+
+	if (points_count < 2)
+		return NULL;
+    if ((palette = malloc(sizeof(Color) * count)) == NULL)
+		return NULL;
+	qsort(points, points_count, sizeof(ControlPoint), st_compar_control_points);
+
+	size_t	point_i = 0;
+
+	double	x0 = points[point_i].position;
+	double	x1 = points[point_i + 1].position;
+
+	double	y0 = points[point_i].color.r;
+	double	y1 = points[point_i + 1].color.r;
+
+	double	delta_x = x1 - x0;
+	double	delta_y = y1 - y0;
+
+	double	m = delta_x / delta_y;
+	double	b = y0 - x0;
+
+	double red = 0;
+	for (int i = 0; i < count; i++)
+	{
+		palette[i].r = (uint8_t)(255.0 * (m * red + b));
+		red += 1.0 / (double)count;
+		if (red >= x1)
+		{
+			if (point_i >= points_count)
+				break;
+			x0 = x1;
+			point_i++;
+			x1 = points[point_i + 1].position;
+		}
+		palette[i].g = 0;
+		palette[i].b = 0;
+		printf("%d\n", i);
+	}
+	return palette;
+}
+
+static int		st_compar_control_points(const void *ptr1, const void *ptr2)
+{
+	const ControlPoint	*point1 = ptr1;
+	const ControlPoint	*point2 = ptr2;
+
+	if (point1->position < point2->position)
+		return -1;
+	if (point1->position > point2->position)
+		return 1;
+	return 0;
+}
+
+static Color	*st_hsl_rainbow(int count)
+{
+	ColorHSL		hsl;
+	Color			*palette;
+
+    if ((palette = malloc(sizeof(Color) * count)) == NULL)
+		return NULL;
     for (int i = 0; i < count; i++)
     {
 		hsl.h = (uint8_t)(255.0 * ((double)i / (double)count));
@@ -27,14 +103,7 @@ unsigned int	color_texture_new(int count)
 		palette[i] = palette[j];
 		palette[j] = tmp;
 	}
-
-	GL_CALL(glGenTextures(1, &texture));
-	GL_CALL(glBindTexture(GL_TEXTURE_1D, texture));
-	GL_CALL(glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST));
-	GL_CALL(glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST));
-	GL_CALL(glTexImage1D(GL_TEXTURE_1D, 0, GL_RGB, count + 1, 0, GL_RGB, GL_UNSIGNED_BYTE, palette));
-	free(palette);
-	return texture;
+	return palette;
 }
 
 static Color	color_hsl_to_rgb(ColorHSL color_hsl)
diff --git a/src/event.c b/src/event.c
index 9d384fc..d5f1180 100644
--- a/src/event.c
+++ b/src/event.c
@@ -6,6 +6,7 @@ static void	st_move_horizontal(State *state, bool move_right);
 static void	st_move_vertical(State *state, bool move_down);
 static void	st_set_key(SDL_Keycode sym, bool value);
 static void	st_apply_keys(State *state);
+static void	st_resize(State *state, int new_width, int new_height);
 
 static bool	g_key_states[] = {
 	[KEY_UP]    = false,
@@ -60,22 +61,37 @@ void 		event_handle(State *state)
 
 			case SDL_WINDOWEVENT:
 				if (e.window.event == SDL_WINDOWEVENT_RESIZED)
-				{
-					double w_ratio = (double)state->width / (double)e.window.data1;
-					double h_ratio = (double)state->height / (double)e.window.data2;
-					SDL_GL_GetDrawableSize(state->window, &state->width, &state->height);
-					GL_CALL(glViewport(0, 0, state->width, state->height));
-					state->real_start /= w_ratio;
-					state->real_end /= w_ratio;
-					state->imag_start /= h_ratio;
-					state->imag_end /= h_ratio;
-				}
+					st_resize(state, e.window.data1, e.window.data2);
 				break;
         }
     }
 	st_apply_keys(state);
 }
 
+void		st_resize(State *state, int new_width, int new_height)
+{
+	double w_delta = ((double)new_width - (double)state->width) / 2.0;
+	double h_delta = ((double)new_height - (double)state->height) / 2.0;
+
+	double real_dist = state->real_end - state->real_start;
+	double imag_dist = state->imag_end - state->imag_start;
+
+	double width_real_ratio =  (double)state->width / real_dist;
+	double height_imag_ratio = (double)state->height / imag_dist;
+
+	w_delta /= width_real_ratio;
+	h_delta /= height_imag_ratio;
+
+	state->real_start -= w_delta;
+	state->real_end   += w_delta;
+
+	state->imag_start -= h_delta;
+	state->imag_end   += h_delta;
+
+	SDL_GL_GetDrawableSize(state->window, &state->width, &state->height);
+	GL_CALL(glViewport(0, 0, state->width, state->height));
+}
+
 static void	st_set_key(SDL_Keycode sym, bool value)
 {
 	switch (sym)
diff --git a/src/state.c b/src/state.c
index f661de6..5df4f02 100644
--- a/src/state.c
+++ b/src/state.c
@@ -54,6 +54,7 @@ bool	state_init(State *state)
 	state->real_end = 2.0;
 	state->imag_start = -2.0;
 	state->imag_end = 2.0;
+
     state->running = true;
 	state->smooth = false;
 	state->samples = 1.0;